Hydrogel electrolytes hold great potential in flexible zinc ion supercapacitors(ZICs)due to their high conductivity,good safety,and flexibility.However,freezing of electrolytes at low temperature(subzero)leads to dras...Hydrogel electrolytes hold great potential in flexible zinc ion supercapacitors(ZICs)due to their high conductivity,good safety,and flexibility.However,freezing of electrolytes at low temperature(subzero)leads to drastic reduction in ionic conductivity and mechanical properties that deteriorates the performance of flexible ZICs.Besides,the mechanical fracture during arbitrary deformations significantly prunes out the lifespan of the flexible device.Herein,a Zn^(2+)and Li^(+)co-doped,polypyrrole-dopamine decorated Sb_(2)S_(3)incorporated,and polyvinyl alcohol/poly(N-(2-hydroxyethyl)acrylamide)double-network hydrogel electrolyte is constructed with favorable mechanical reliability,anti-freezing,and self-healing ability.In addition,it delivers ultra-high ionic conductivity of 8.6 and 3.7 S m^(-1)at 20 and−30°C,respectively,and displays excellent mechanical properties to withstand tensile stress of 1.85 MPa with tensile elongation of 760%,together with fracture energy of 5.14 MJ m^(-3).Notably,the fractured hydrogel electrolyte can recover itself after only 90 s of infrared illumination,while regaining 83%of its tensile strain and almost 100%of its ionic conductivity during−30–60°C.Moreover,ZICs coupled with this hydrogel electrolyte not only show a wide voltage window(up to 2 V),but also provide high energy density of 230 Wh kg^(-1)at power density of 500 W kg^(-1)with a capacity retention of 86.7%after 20,000 cycles under 20°C.Furthermore,the ZICs are able to retain excellent capacity even under various mechanical deformation at−30°C.This contribution will open up new insights into design of advanced wearable flexible electronics with environmental adaptability and long-life span.展开更多
Compared with traditional piezoelectric ultrasonic devices,optoacoustic devices have unique advantages such as a simple preparation process,anti-electromagnetic interference,and wireless long-distance power supply.How...Compared with traditional piezoelectric ultrasonic devices,optoacoustic devices have unique advantages such as a simple preparation process,anti-electromagnetic interference,and wireless long-distance power supply.However,current optoacoustic devices remain limited due to a low damage threshold and energy conversion efficiency,which seriously hinder their widespread applications.In this study,using a self-healing polydimethylsiloxane(PDMS,Fe-Hpdca-PDMS)and carbon nanotube composite,a flexible optoacoustic patch is developed,which possesses the self-healing capability at room temperature,and can even recover from damage induced by cutting or laser irradiation.Moreover,this patch can generate high-intensity ultrasound(>25 MPa)without the focusing structure.The laser damage threshold is greater than 183.44 mJ cm^(-2),and the optoacoustic energy conversion efficiency reaches a major achievement at 10.66×10^(-3),compared with other carbon-based nanomaterials and PDMS composites.This patch is also been successfully examined in the application of acoustic flow,thrombolysis,and wireless energy harvesting.All findings in this study provides new insight into designing and fabricating of novel ultrasound devices for biomedical applications.展开更多
Phase change materials(PCMs) present promising potential for guaranteeing safety in thermal management systems.However,most reported PCMs have a single application in energy storage for thermal management systems,whic...Phase change materials(PCMs) present promising potential for guaranteeing safety in thermal management systems.However,most reported PCMs have a single application in energy storage for thermal management systems,which does not meet the growing demand for multi-functional materials.In this paper,the flexible material and hydrogen-bonding function are innovatively combined to design and prepare a novel multi-functional flexible phase change film(PPL).The 0.2PPL-2 film exhibits solid-solid phase change behavior with energy storage density of 131.8 J/g at the transition temperature of42.1℃,thermal cycling stability(500 cycles),wide-temperature range flexibility(0-60℃) and selfhealing property.Notably,the PPL film can be recycled up to 98.5% by intrinsic remodeling.Moreover,the PPL film can be tailored to the desired colors and configurations and can be cleverly assembled on several thermal management systems at ambient temperature through its flexibility combined with shape-memory properties.More interestingly,the transmittance of PPL will be altered when the ambient temperature changes(60℃),conveying a clear thermal signal.Finally,the thermal energy storage performance of the PPL film is successfully tested by human thermotherapy and electronic device temperature control experiments.The proposed functional integration strategy provides innovative ideas to design PCMs for multifunctionality,and makes significant contributions in green chemistry,highefficiency thermal management,and energy sustainability.展开更多
The serious environmental threat caused by petroleum-based plastics has spurred more researches in developing substitutes from renewable sources.Starch is desirable for fabricating bioplastic due to its abundance and ...The serious environmental threat caused by petroleum-based plastics has spurred more researches in developing substitutes from renewable sources.Starch is desirable for fabricating bioplastic due to its abundance and renewable nature.However,limitations such as brittleness,hydrophilicity,and thermal properties restrict its widespread application.To overcome these issues,covalent adaptable network was constructed to fabricate a fully bio-based starch plastic with multiple advantages via Schiff base reactions.This strategy endowed starch plastic with excellent thermal processability,as evidenced by a low glass transition temperature(T_(g)=20.15℃).Through introducing Priamine with long carbon chains,the starch plastic demonstrated superior flexibility(elongation at break=45.2%)and waterproof capability(water contact angle=109.2°).Besides,it possessed a good thermal stability and self-adaptability,as well as solvent resistance and chemical degradability.This work provides a promising method to fabricate fully bio-based plastics as alternative to petroleum-based plastics.展开更多
The anti-freezing strategy of hydrogels and their self-healing structure are often contradictory,it is vital to break through the molecular structure to design and construct hydrogels with intrinsic anti-freezing/self...The anti-freezing strategy of hydrogels and their self-healing structure are often contradictory,it is vital to break through the molecular structure to design and construct hydrogels with intrinsic anti-freezing/self-healing for meeting the rapid development of flexible and wearable devices in diverse service conditions.Herein,we design a new hydrogel electrolyte(AF/SH-Hydrogel)with intrinsic anti-freezing/self-healing capabilities by introducing ethylene glycol molecules,dynamic chemical bonding(disulfide bond),and supramolecular interaction(multi-hydrogen bond)into the polyacrylamide molecular chain.Thanks to the exceptional freeze resistance(84%capacity retention at-20℃)and intrinsic self-healing capabilities(95%capacity retention after 5 cutting/self-healing cycles),the obtained AF/SH-Hydrogel makes the zinc||manganese dioxide cell an economically feasible battery for the state-of-the-art applications.The Zn||AF/SH-Hydrogel||MnO_(2)device offers a near-theoretical specific capacity of 285 m A h g^(-1)at 0.1 A g^(-1)(Coulombic efficiency≈100%),as well as good self-healing capability and mechanical flexibility in an ice bath.This work provides insight that can be utilized to develop multifunctional hydrogel electrolytes for application in next generation of self-healable and freeze-resistance smart aqueous energy storage devices.展开更多
The requisite functions of a bentonite buffer in a deep geological repository depend on the sealing/healing of bentonite interfaces,with particular emphasis on the self-healing(automatic healing upon wetting)of assemb...The requisite functions of a bentonite buffer in a deep geological repository depend on the sealing/healing of bentonite interfaces,with particular emphasis on the self-healing(automatic healing upon wetting)of assembled bentonite-bentonite interfaces.This study determined the shear resistance(including the peak shear strength and secant modulus)of densely compacted Gaomiaozi(GMZ)bentonite and its assembled interface after confined water saturation.The effect of bentonite dry density and saturation time on the shear resistance of saturated healed interfaces was elucidated,and the interfacial self-healing capacity was assessed.The results indicate that the shear resistance of the saturated healed interfaces increased with the bentonite dry density but had a non-monotonic correlation with the saturation time.For a given dry density of the bentonite,the saturated healed interface exhibits a lower peak shear strength than the saturated intact bentonite but a higher peak shear strength than the saturated separated interface.The saturated healed and separated interfaces have comparable shear moduli(secant moduli),which are lower than that of the saturated intact bentonite.The saturated healed interfaces display smooth shear failure planes,while the saturated assembled interfaces and intact bentonite exhibit comparable frictional angles.This indicates that interfacial self-healing plays a pivotal role in enhancing interfacial peak shear strength by facilitating microstructural bonding at the assembled interface.Finally,it can be stated that densely compacted GMZ bentonite has a robust interfacial self-healing capacity in terms of shear resistance.These findings contribute to the design of the bentonite buffer and facilitate the evaluation of its safe operation at specified disposal ages.展开更多
Experiments were conducted to evaluate the healing of drying cracks in air-dried bentonite-sand blocks after hydration and swelling in groundwater,providing justifications to simplify the protection of blocks prior to...Experiments were conducted to evaluate the healing of drying cracks in air-dried bentonite-sand blocks after hydration and swelling in groundwater,providing justifications to simplify the protection of blocks prior to installation in a high-level radioactive waste repository.Synthetic groundwater was prepared to represent the geochemistry of Beishan groundwater,and was used to hydrate the blocks during the swelling pressure and swelling strain measurements,as Beishan is the most promising site for China's repository.Healing of the surface cracks was recorded by photography,and healing of the internal cracks was visualized by CT images and hydraulic conductivity of air-dried blocks.The results indicate that the maximum swelling pressure and swelling strain are primarily affected by the geochemistry of Beishan groundwater,but not affected by the drying cracks.The maximum swelling pressure and swelling strain of air-dried blocks are comparable to or even higher than the pressure and strain of fresh blocks.The maximum swelling pressure measured in strong(i.e.high ion strength)Beishan groundwater was 44%of the pressure measured in deionized(DI)water,and the maximum swelling strain was reduced to 23%of the strain measured in DI water.Nevertheless,the remained swelling of the blocks hydrated in strong Beishan groundwater was sufficient to heal the surface and internal drying cracks,as demonstrated by the pictures of surface cracks and CT images.The hydraulic conductivity of the air-dried block permeated with strong groundwater was comparable(3.7×higher)to the hydraulic conductivity of the fresh block,indicating the self-healing of drying cracks after hydration and swelling in groundwater.A simplified method of protecting the block with plastic wraps before installation is recommended,since the remained swelling of the block hydrated in Beishan groundwater is sufficient to heal the drying cracks.展开更多
The occurrence of ultrafiltration(UF)membrane fouling frequently hampers the sustainable advancement of UF technology.Reactive self-cleaning UF membranes can effectively alleviate the problem of membrane fouling.Never...The occurrence of ultrafiltration(UF)membrane fouling frequently hampers the sustainable advancement of UF technology.Reactive self-cleaning UF membranes can effectively alleviate the problem of membrane fouling.Nevertheless,the self-cleaning process may accelerate membrane aging.Addressing these concerns,we present an innovative design concept for composite self-healing materials based on self-cleaning UF membranes.To begin,TiO_(2)nanoparticles were incorporated into the polymer molecular structure via molecular design,resulting in the synthesis of TiO_(2)/carboxyl-polyether sulfone(PES)hybrid materials.Subsequently,the nonsolvent-induced phase inversion technique was employed to prepare a novel of UF membrane.Lastly,a polyvinyl alcohol(PVA)hydrogel coating was applied to the hybrid UF membrane surface to create PVA@TiO_(2)/carboxyl-PES self-healing reactive UF membranes.By establishing a covalent bond,the TiO_(2)nanoparticles were effectively and uniformly dispersed within the UF membrane,leading to exceptional self-cleaning properties.Furthermore,the water-absorbing and swelling properties of PVA hydrogel,along with its capacity to form hydrogen bonds with water molecules,resulted in UF membranes with improved hydrophilicity and active self-healing abilities.The results demonstrated that the water contact angle of PVA@5%TiO_(2)/carboxyl-PES UF membrane was 43.1°.Following a 1-h exposure to simulated solar exposure,the water flux recovery ratio increased from 48.16%to 81.03%.Moreover,even after undergoing five cycles of 12-h simulated sunlight exposure,the UF membranes exhibited a consistent retention rate of over 97%,thus fully demonstrating their exceptional self-cleaning,antifouling,and selfhealing capabilities.We anticipate that the self-healing reactive UF membrane system will serve as a pioneering and comprehensive solution for the self-cleaning antifouling challenges encountered in UF membranes while also effectively mitigating the aging effects of reactive UF membranes.展开更多
Hydrogels exhibit potential applications in smart wearable devices because of their exceptional sensitivity to various external stimuli.However,their applications are limited by challenges in terms of issues in biocom...Hydrogels exhibit potential applications in smart wearable devices because of their exceptional sensitivity to various external stimuli.However,their applications are limited by challenges in terms of issues in biocompatibility,custom shape,and self-healing.Herein,a conductive,stretchable,adaptable,self-healing,and biocompatible liquid metal GaInSn/Ni-based composite hydrogel is developed by incorporating a magnetic liquid metal into the hydrogel framework through crosslinking polyvinyl alcohol(PVA)with sodium tetraborate.The excellent stretchability and fast self-healing capability of the PVA/liquid metal hydrogel are derived from its abundant hydrogen binding sites and liquid metal fusion.Significantly,owing to the magnetic constituent,the PVA/liquid metal hydrogel can be guided remotely using an external magnetic field to a specific position to repair the broken wires with no need for manual operation.The composite hydrogel also exhibits sensitive deformation responses and can be used as a strain sensor to monitor various body motions.Additionally,the multifunctional hydrogel displays absorption-dominated electromagnetic interference(EMI)shielding properties.The total shielding performance of the composite hydrogel increases to~62.5 dB from~31.8 dB of the pure PVA hydrogel at the thickness of 3.0 mm.The proposed bioinspired multifunctional magnetic hydrogel demonstrates substantial application potential in the field of intelligent wearable devices.展开更多
The booming wearable/portable electronic devices industry has stimulated the progress of supporting flexible energy storage devices.Excellent performance of flexible devices not only requires the component units of ea...The booming wearable/portable electronic devices industry has stimulated the progress of supporting flexible energy storage devices.Excellent performance of flexible devices not only requires the component units of each device to maintain the original performance under external forces,but also demands the overall device to be flexible in response to external fields.However,flexible energy storage devices inevitably occur mechanical damages(extrusion,impact,vibration)/electrical damages(overcharge,over-discharge,external short circuit)during longterm complex deformation conditions,causing serious performance degradation and safety risks.Inspired by the healing phenomenon of nature,endowing energy storage devices with self-healing capability has become a promising strategy to effectively improve the durability and functionality of devices.Herein,this review systematically summarizes the latest progress in intrinsic self-healing chemistry for energy storage devices.Firstly,the main intrinsic self-healing mechanism is introduced.Then,the research situation of electrodes,electrolytes,artificial interface layers and integrated devices based on intrinsic self-healing and advanced characterization technology is reviewed.Finally,the current challenges and perspective are provided.We believe this critical review will contribute to the development of intrinsic self-healing chemistry in the flexible energy storage field.展开更多
Today,self-healing graphene-and MXene-based composites have attracted researchers due to the increase in durability as well as the cost reduction in long-time applications.Different studies have focused on designing n...Today,self-healing graphene-and MXene-based composites have attracted researchers due to the increase in durability as well as the cost reduction in long-time applications.Different studies have focused on designing novel self-healing graphene-and MXenebased composites with enhanced sensitivity,stretchability,and flexibility as well as improved electrical conductivity,healing efficacy,mechanical properties,and energy conversion efficacy.These composites with self-healing properties can be employed in the field of wearable sensors,supercapacitors,anticorrosive coatings,electromagnetic interference shielding,electronic-skin,soft robotics,etc.However,it appears that more explorations are still needed to achieve composites with excellent arbitrary shape adaptability,suitable adhesiveness,ideal durability,high stretchability,immediate self-healing responsibility,and outstanding electromagnetic features.Besides,optimizing reaction/synthesis conditions and finding suitable strategies for functionalization/modification are crucial aspects that should be comprehensively investigated.MXenes and graphene exhibited superior electrochemical properties with abundant surface terminations and great surface area,which are important to evolve biomedical and sensing applications.However,flexibility and stretchability are important criteria that need to be improved for their future applications.Herein,the most recent advancements pertaining to the applications and properties of self-healing graphene-and MXene-based composites are deliberated,focusing on crucial challenges and future perspectives.展开更多
Coating technologies are a commonly used way to protect metals against corrosion.However,with more and more severe service environments of materials,many protective coating systems often are not environmentally friend...Coating technologies are a commonly used way to protect metals against corrosion.However,with more and more severe service environments of materials,many protective coating systems often are not environmentally friendly or toxic as in the case of chromates.Based on the world’s abundant ideal magnesium(Mg)and its alloy,the smart self-healing anticorrosive coating can autonomously restore the damaged part of the coating according to the environmental changes,strengthen the corrosion protection ability,and prolong its service life.This paper reviews the research progress of smart self-healing coatings on Mg alloys.These coatings mostly contain suitable corrosion inhibitors encapsulated into micro/nano containers.Moreover,the different self-healing mechanisms and functionalities of micro/nano containers are discussed.The micro/nano containers range from inorganic nanocontainers such as mesoporous nanoparticles(silica(SiO_(2)),titanium dioxide(TiO_(2)),etc.),over inorganic clays(halloysite,hydrotalcite-like,zeolite),to organic nanocontainers such as polymer microcapsules,nanofibers,chitosan(CS)and cyclodextrin(CD),as well as,carbon materials such as graphene and carbon nanotubes and hybrids such as metal organic frameworks.The functioning of micro/nano containers can be divided in two principal groups:autonomous(based on defect filling and corrosion inhibition)and non-autonomous(based on dynamic bonds and shape memory polymers).Moreover,multi functionalities and composite applications of various micro/nano containers are summarized.At present,significant progress has been made in the preparation methods and technologies of micro/nano containers.Achieving long-term self-healing properties of coatings sensing of coating failure and early warning after self-healing function failure can be expected as the main development direction of self-healing corrosion protection coatings in the future.展开更多
Gallium oxide(Ga_(2)O_(3))based flexible heterojunction type deep ultraviolet(UV)photodetectors show excellent solar-blind photoelectric performance,even when not powered,which makes them ideal for use in intelligent ...Gallium oxide(Ga_(2)O_(3))based flexible heterojunction type deep ultraviolet(UV)photodetectors show excellent solar-blind photoelectric performance,even when not powered,which makes them ideal for use in intelligent wearable devices.How-ever,traditional flexible photodetectors are prone to damage during use due to poor toughness,which reduces the service life of these devices.Self-healing hydrogels have been demonstrated to have the ability to repair damage and their combination with Ga_(2)O_(3) could potentially improve the lifetime of the flexible photodetectors while maintaining their performance.Herein,a novel self-healing and self-powered flexible photodetector has been constructed onto the hydrogel substrate,which exhibits an excellent responsivity of 0.24 mA/W under 254 nm UV light at zero bias due to the built-in electric field originating from the PEDOT:PSS/Ga_(2)O_(3) heterojunction.The self-healing of the Ga_(2)O_(3) based photodetector was enabled by the reversible property of the synthesis of agarose and polyvinyl alcohol double network,which allows the photodetector to recover its original configu-ration and function after damage.After self-healing,the photocurrent of the photodetector decreases from 1.23 to 1.21μA,while the dark current rises from 0.95 to 0.97μA,with a barely unchanged of photoresponse speed.Such a remarkable recov-ery capability and the photodetector’s superior photoelectric performance not only significantly enhance a device lifespan but also present new possibilities to develop wearable and intelligent electronics in the future.展开更多
The advance of microelectronics requires the micropower of microsupercapacitors(MSCs) to possess wide temperature-and damage-tolerance beyond high areal energy density.The properties of electrolyte are crucial for MSC...The advance of microelectronics requires the micropower of microsupercapacitors(MSCs) to possess wide temperature-and damage-tolerance beyond high areal energy density.The properties of electrolyte are crucial for MSCs to meet the above requirements.Here,an organohydrogel electrolyte,featured with high salt tolerance,ultralow freezing point,and strong self-healing ability,is experimentally realized via modulating its inner dynamic bonds.Spectroscopic and theoretical analysis reveal that dimethyl sulfoxide has the ability to reconstruct Li^(+)solvation structure,and interact with free water and polyvinyl alcohol chains via forming hydrogen bonds.The organohydrogel electrolyte is employed to build MSCs,which show a boosted energy density,promising wide temperature range-and damage-tolerant ability.These attractive features make the designed organohydrogel electrolyte have great potential to advance MSCs.展开更多
In this study,we proposed a self-healing conductive hydrogel based on polysaccharides and Li+to serve as flexible sensors.At first,the oxidized sodium alginate(OSA)was obtained through the oxidation reaction of sodium...In this study,we proposed a self-healing conductive hydrogel based on polysaccharides and Li+to serve as flexible sensors.At first,the oxidized sodium alginate(OSA)was obtained through the oxidation reaction of sodium alginate(SA).Then OSA,carboxymethyl chitosan(CMC),and agarose(AGO)were dissolved in LiCl solution,respectively.Finally,the hydrogel was obtained through heating,mixing,and cooling processes.Because of the Schiff base structure and hydrogen bonding,the hydrogel demonstrates good mechanical and self-healing properties.The presence of Li+provides good conductivity for the hydrogel.In addition,we demonstrated the application of the hydrogel as the flexible sensors.It can perceive the process of pressing Morse code with the index finger as a pressure sensor and monitor sliding movement of the thumb as the strain sensor to browse the web with the mobile phone.Thus,the selfhealing conductive hydrogel may have potential applications in flexible wearable sensors.展开更多
Magnesium(Mg) alloys are well-known in biomedical materials owing to their elastic module near to bone, biocompatibility and biodegradation properties. Nevertheless, poor corrosion resistance hinders their biomedical ...Magnesium(Mg) alloys are well-known in biomedical materials owing to their elastic module near to bone, biocompatibility and biodegradation properties. Nevertheless, poor corrosion resistance hinders their biomedical applications. Besides, it is necessary to endow Mg alloys with bioactive property, which is crucial for temporary bone implants. Here, a self-healing, corrosion resistant and bioactive duplex coating of plasma electrolytic oxidization(PEO)/polydopamine(PDA) is applied on AZ91 substrate using PEO and subsequent electrodeposition process. Moreover, the role of different electrodeposition times(60 s, 120 s) and dopamine concentrations(1 and 1.5 mg/ml) to improve corrosion resistance, bioactivity, biocompatibility and self-healing property and its mechanism are investigated. The results indicate that the PEO coating is efficiently sealed by the PDA, depending on the electrodeposition parameters. Noticeably, electrodeposition for 120 s in dopamine concentration of 1 mg/ml(120T-1C) results in the formation of uniform and crack-free PDA coating. Duplex PEO/PDA coatings reveal high bioactivity compared to PEO coating, owing to electrostatic interaction between PDA top-layer and calcium and phosphate ions as well as high hydrophilicity of coatings. In addition, duplex PEO/PDA coatings also show improved and more stable protective performance than the PEO and bare alloy, depending on the PDA deposition parameters. Noticeably, the corrosion current density of the 120T-1C decreases one orders of magnitude compared to PEO. In addition, the presence of a broad passivation region in the anodic polarization branch shows durable self-healing property via Zipper-like mechanism, demonstrating the duplex coating could preserve promising corrosion resistance.Furthermore, the cytocompatibility of duplex coated samples is also confirmed via interaction with MG63 cells. In summary, the PEO/PDA coating with great corrosion protection, self-healing ability, bioactivity and biocompatibility could be a promising candidate for degradable magnesium-based implants.展开更多
In order to investigate the behavior characteristics of asphalt components during the process of nano-cracks temperature self-healing(NTS),molecular simulation technology was used to simulate the temperature self-heal...In order to investigate the behavior characteristics of asphalt components during the process of nano-cracks temperature self-healing(NTS),molecular simulation technology was used to simulate the temperature self-healing of asphalt.Based on the determination of asphalts(virgin asphalt and aged asphalt),the proportional changes of asphalt components were confirmed.The distribution characteristics of asphalt components were obtained by marking different components in the process of NTS.At the same time,the rationality of the micro simulation findings was confirmed by asphalt performance tests and infrared spectroscopy results.The results show that different asphalt components have different behavior characteristics in the process of NTS.The content of asphaltene and resin plays a key role in the process of NTS,while saturation and aromatics play an active role in the temperature self-healing before and after aging.The NTS is the result of the comprehensive action of different components,and the self-healing efficiency is proportional to the relative molecular mass.The effect of aging on the NTS is also realized by changing the proportion of asphalt components.展开更多
Bioinspired by Nepenthes, lubricant infused surfaces(LIS) have attracted widespread attention in the field of anticorrosion. However,the lubricant coating has some disadvantages such as complex construction processing...Bioinspired by Nepenthes, lubricant infused surfaces(LIS) have attracted widespread attention in the field of anticorrosion. However,the lubricant coating has some disadvantages such as complex construction processing and easy loss of oil phase in air or dynamic water phase. In this study, oleogel is infused into a lotus leaf inspired super-hydrophobic matrix to form an oleogel infused surface(OIS) for enhancing corrosion resistance of active Mg-Li alloy. For reserving oleogel, firstly, a facile one-step electrodeposition method is used to construct super-hydrophobic surface(SHS) composed by samarium/myristic acid complex micro-nano flower structure onto Mg-Li alloy.The coating exhibits excellent superhydrophobic property at a static contact angle of 160° by applying 30 V electrolysis for 30 min. The protection efficiency of single SHS highly relates with the metal itself. For short period immersion in water phase, SHS can afford protection to Mg-Li alloy. However, the long-term immersion will see the rapid failure of SHS, and the high activity of Mg-Li alloy is one main reason.We assume that SHS cannot be a good choice for protecting Mg-Li alloy. Then, a Nepenthes inspired liquid coating is formed by infusing oleogel into the micro-nano structure by a spin-coating method. The liquid coating performs prominent corrosion resistance with Rctreaching as high as 1.51 × 10^(10)Ω cm^(2). After the mechanical damage from the external environment, the liquid coating can realize self-repair through thermal assistance, and the liquid coating can still restore Rctup to 1.24 × 10^(10)Ω cm^(2) after healing. The corrosion resistance of the liquid coating remains strong by showing Rctas high as 1.14 × 10^(9)Ω cm^(2), even after immersion in representative corrosive 3.5 wt% Na Cl solution for 30 d.展开更多
Ionic gels can be potentially used in wearable devices owing to their high humidity resistance and non-volatility.However,the applicability of existing ionic gel pressure sensors is limited by their low sensitivity.Th...Ionic gels can be potentially used in wearable devices owing to their high humidity resistance and non-volatility.However,the applicability of existing ionic gel pressure sensors is limited by their low sensitivity.Therefore,it is very import-ant to develop an ionic gel pressure sensor with high sensitivity and a wide pressure detection range without sacrificing mechan-ical stretchability and self-healing ability.Herein,we report an effective strategy for developing pressure sensors based on ion-ic gel composites consisting of high-molecular-weight polymers,ionic liquids,and Au nanoparticles.The resulting capacitive pressure sensors exhibit high pressure sensitivity,fast response,and excellent self-healing properties.The sensors composed of highly hydrophobic polymers and ionic liquids can be used to track underwater movements,demonstrating broad application prospects in human motion state monitoring and underwater mechanical operations.展开更多
Surface coatings have been extensively used to control the degradation rate of Mg alloys for bioimplant applications.However,these coatings only act as passive barriers.In corrosive media,structural damage impairs the...Surface coatings have been extensively used to control the degradation rate of Mg alloys for bioimplant applications.However,these coatings only act as passive barriers.In corrosive media,structural damage impairs their barrier properties,resulting in rapid degradation of Mg alloys.The present study incorporates phytic acid(PA)as a healing agent in polycaprolactone(PCL)microcapsules with a unique honeycomb core matrix to obtain a self-healing PA-PCLcaps coating.The contact between simulated body fluid(SBF)and PA-PCLcaps coated ZM21 exhibited Cassie-Baxter interfacial states,resulting in significant hydrophobicity with a contact angle(CA)of 116.3.The corrosion potential(Ecorr)and current density(Icorr)were found to be-0.28 V and 1.1×10^(-9)A/cm^(2),respectively,for PA-PCLcaps coating,resulting in biosafe corrosion rate of 2.5×10^(-4)mm/year.After mechanical scratching,rapid HA mineralization at scratched regions recovered the hydrogen evolution rate(HER,0.36 mL/cm^(2)/day)and pH change(pH 7.10)of scratched PA-PCLcaps coated ZM21 samples to corresponding unscratched samples within one day of immersion.The coating’s self-healing ability could be attributed to PA released from punctured microcapsules,which facilitates HA chelation.The pH-triggered(pH 10)and Mg(II)-triggered(5 mM)conditions enhanced PA release from PA-PCLcaps coating by 2.5 and 3.1 times,respectively.As a result,dense HA mineralization occurred,which protects the coating from structural defects and ensures its durability in stimulating conditions.The findings of present study provide new insight for design of multiple stimuli-feedback based self-healing coatings on biodegradable Mg alloys.展开更多
基金supported by the National Natural Science Foundation of China(52174247 and 22302066)“Hejian”Innovative Talent Project of Hunan Province(No.2022RC1088)+1 种基金the Hunan Provincial Natural Science Foundation(2023JJ40255)the Scientific Research Foundation of Hunan Provincial Education(22B0599 and 23A0442)。
文摘Hydrogel electrolytes hold great potential in flexible zinc ion supercapacitors(ZICs)due to their high conductivity,good safety,and flexibility.However,freezing of electrolytes at low temperature(subzero)leads to drastic reduction in ionic conductivity and mechanical properties that deteriorates the performance of flexible ZICs.Besides,the mechanical fracture during arbitrary deformations significantly prunes out the lifespan of the flexible device.Herein,a Zn^(2+)and Li^(+)co-doped,polypyrrole-dopamine decorated Sb_(2)S_(3)incorporated,and polyvinyl alcohol/poly(N-(2-hydroxyethyl)acrylamide)double-network hydrogel electrolyte is constructed with favorable mechanical reliability,anti-freezing,and self-healing ability.In addition,it delivers ultra-high ionic conductivity of 8.6 and 3.7 S m^(-1)at 20 and−30°C,respectively,and displays excellent mechanical properties to withstand tensile stress of 1.85 MPa with tensile elongation of 760%,together with fracture energy of 5.14 MJ m^(-3).Notably,the fractured hydrogel electrolyte can recover itself after only 90 s of infrared illumination,while regaining 83%of its tensile strain and almost 100%of its ionic conductivity during−30–60°C.Moreover,ZICs coupled with this hydrogel electrolyte not only show a wide voltage window(up to 2 V),but also provide high energy density of 230 Wh kg^(-1)at power density of 500 W kg^(-1)with a capacity retention of 86.7%after 20,000 cycles under 20°C.Furthermore,the ZICs are able to retain excellent capacity even under various mechanical deformation at−30°C.This contribution will open up new insights into design of advanced wearable flexible electronics with environmental adaptability and long-life span.
基金This work was supported by the Natural Science Foundation of China(Grant no.U22A20259,12102140)the Shenzhen Basic Science Research(No.JCYJ20200109110006136)the China Postdoctoral Science Foundation(No.2022M721258).We also thank the Analytical and Testing Center of Huazhong University of Science&Technology.
文摘Compared with traditional piezoelectric ultrasonic devices,optoacoustic devices have unique advantages such as a simple preparation process,anti-electromagnetic interference,and wireless long-distance power supply.However,current optoacoustic devices remain limited due to a low damage threshold and energy conversion efficiency,which seriously hinder their widespread applications.In this study,using a self-healing polydimethylsiloxane(PDMS,Fe-Hpdca-PDMS)and carbon nanotube composite,a flexible optoacoustic patch is developed,which possesses the self-healing capability at room temperature,and can even recover from damage induced by cutting or laser irradiation.Moreover,this patch can generate high-intensity ultrasound(>25 MPa)without the focusing structure.The laser damage threshold is greater than 183.44 mJ cm^(-2),and the optoacoustic energy conversion efficiency reaches a major achievement at 10.66×10^(-3),compared with other carbon-based nanomaterials and PDMS composites.This patch is also been successfully examined in the application of acoustic flow,thrombolysis,and wireless energy harvesting.All findings in this study provides new insight into designing and fabricating of novel ultrasound devices for biomedical applications.
基金supported by the Project of Shanghai Science and Technology Commission (Grant No. 19DZ1203102)National Key Research and Development Project (2018YFD0401300)Shanghai Municipal Science and Technology Project (16040501600)。
文摘Phase change materials(PCMs) present promising potential for guaranteeing safety in thermal management systems.However,most reported PCMs have a single application in energy storage for thermal management systems,which does not meet the growing demand for multi-functional materials.In this paper,the flexible material and hydrogen-bonding function are innovatively combined to design and prepare a novel multi-functional flexible phase change film(PPL).The 0.2PPL-2 film exhibits solid-solid phase change behavior with energy storage density of 131.8 J/g at the transition temperature of42.1℃,thermal cycling stability(500 cycles),wide-temperature range flexibility(0-60℃) and selfhealing property.Notably,the PPL film can be recycled up to 98.5% by intrinsic remodeling.Moreover,the PPL film can be tailored to the desired colors and configurations and can be cleverly assembled on several thermal management systems at ambient temperature through its flexibility combined with shape-memory properties.More interestingly,the transmittance of PPL will be altered when the ambient temperature changes(60℃),conveying a clear thermal signal.Finally,the thermal energy storage performance of the PPL film is successfully tested by human thermotherapy and electronic device temperature control experiments.The proposed functional integration strategy provides innovative ideas to design PCMs for multifunctionality,and makes significant contributions in green chemistry,highefficiency thermal management,and energy sustainability.
基金supported by the National Natural Science Foundation of China(U23A6005 and 32171721)State Key Laboratory of Pulp and Paper Engineering(202305,2023ZD01,2023C02)+1 种基金Guangdong Province Basic and Application Basic Research Fund(2023B1515040013)the Fundamental Research Funds for the Central Universities(2023ZYGXZR045).
文摘The serious environmental threat caused by petroleum-based plastics has spurred more researches in developing substitutes from renewable sources.Starch is desirable for fabricating bioplastic due to its abundance and renewable nature.However,limitations such as brittleness,hydrophilicity,and thermal properties restrict its widespread application.To overcome these issues,covalent adaptable network was constructed to fabricate a fully bio-based starch plastic with multiple advantages via Schiff base reactions.This strategy endowed starch plastic with excellent thermal processability,as evidenced by a low glass transition temperature(T_(g)=20.15℃).Through introducing Priamine with long carbon chains,the starch plastic demonstrated superior flexibility(elongation at break=45.2%)and waterproof capability(water contact angle=109.2°).Besides,it possessed a good thermal stability and self-adaptability,as well as solvent resistance and chemical degradability.This work provides a promising method to fabricate fully bio-based plastics as alternative to petroleum-based plastics.
基金supported by the link project of the National Natural Science Foundation of China(52002052 and 22209020)the Key Research and Development Project of Science and Technology Department of Sichuan Province(2022YFSY0004)+2 种基金the Opening project of the State Key Laboratory of New Textile Materials and Advanced Processing Technology(FZ2021009)the Natural Science Foundation of Sichuan Province(2023NSFSC0995)the Natural Science Foundation of Hunan Province(2022JJ30227)。
文摘The anti-freezing strategy of hydrogels and their self-healing structure are often contradictory,it is vital to break through the molecular structure to design and construct hydrogels with intrinsic anti-freezing/self-healing for meeting the rapid development of flexible and wearable devices in diverse service conditions.Herein,we design a new hydrogel electrolyte(AF/SH-Hydrogel)with intrinsic anti-freezing/self-healing capabilities by introducing ethylene glycol molecules,dynamic chemical bonding(disulfide bond),and supramolecular interaction(multi-hydrogen bond)into the polyacrylamide molecular chain.Thanks to the exceptional freeze resistance(84%capacity retention at-20℃)and intrinsic self-healing capabilities(95%capacity retention after 5 cutting/self-healing cycles),the obtained AF/SH-Hydrogel makes the zinc||manganese dioxide cell an economically feasible battery for the state-of-the-art applications.The Zn||AF/SH-Hydrogel||MnO_(2)device offers a near-theoretical specific capacity of 285 m A h g^(-1)at 0.1 A g^(-1)(Coulombic efficiency≈100%),as well as good self-healing capability and mechanical flexibility in an ice bath.This work provides insight that can be utilized to develop multifunctional hydrogel electrolytes for application in next generation of self-healable and freeze-resistance smart aqueous energy storage devices.
基金supported by the National Natural Science Foundation of China (Grant Nos.42125701 and 41977232)China Postdoctoral Science Foundation (Grant No.2021M702234).
文摘The requisite functions of a bentonite buffer in a deep geological repository depend on the sealing/healing of bentonite interfaces,with particular emphasis on the self-healing(automatic healing upon wetting)of assembled bentonite-bentonite interfaces.This study determined the shear resistance(including the peak shear strength and secant modulus)of densely compacted Gaomiaozi(GMZ)bentonite and its assembled interface after confined water saturation.The effect of bentonite dry density and saturation time on the shear resistance of saturated healed interfaces was elucidated,and the interfacial self-healing capacity was assessed.The results indicate that the shear resistance of the saturated healed interfaces increased with the bentonite dry density but had a non-monotonic correlation with the saturation time.For a given dry density of the bentonite,the saturated healed interface exhibits a lower peak shear strength than the saturated intact bentonite but a higher peak shear strength than the saturated separated interface.The saturated healed and separated interfaces have comparable shear moduli(secant moduli),which are lower than that of the saturated intact bentonite.The saturated healed interfaces display smooth shear failure planes,while the saturated assembled interfaces and intact bentonite exhibit comparable frictional angles.This indicates that interfacial self-healing plays a pivotal role in enhancing interfacial peak shear strength by facilitating microstructural bonding at the assembled interface.Finally,it can be stated that densely compacted GMZ bentonite has a robust interfacial self-healing capacity in terms of shear resistance.These findings contribute to the design of the bentonite buffer and facilitate the evaluation of its safe operation at specified disposal ages.
基金supported by the National Natural Science Foundation of China(Grant No.41972265)the Fundamental Research Funds for the Central Universities(Grant No.lzujbky-2021-57)+1 种基金the Gansu Province Science Foundation(Grant No.20JR10RA492)Special thanks to the Environmental Research and Education Foundation for supporting the first author(Y.Tan)through a fellowship for his study at the University of Wisconsin-Madison.
文摘Experiments were conducted to evaluate the healing of drying cracks in air-dried bentonite-sand blocks after hydration and swelling in groundwater,providing justifications to simplify the protection of blocks prior to installation in a high-level radioactive waste repository.Synthetic groundwater was prepared to represent the geochemistry of Beishan groundwater,and was used to hydrate the blocks during the swelling pressure and swelling strain measurements,as Beishan is the most promising site for China's repository.Healing of the surface cracks was recorded by photography,and healing of the internal cracks was visualized by CT images and hydraulic conductivity of air-dried blocks.The results indicate that the maximum swelling pressure and swelling strain are primarily affected by the geochemistry of Beishan groundwater,but not affected by the drying cracks.The maximum swelling pressure and swelling strain of air-dried blocks are comparable to or even higher than the pressure and strain of fresh blocks.The maximum swelling pressure measured in strong(i.e.high ion strength)Beishan groundwater was 44%of the pressure measured in deionized(DI)water,and the maximum swelling strain was reduced to 23%of the strain measured in DI water.Nevertheless,the remained swelling of the blocks hydrated in strong Beishan groundwater was sufficient to heal the surface and internal drying cracks,as demonstrated by the pictures of surface cracks and CT images.The hydraulic conductivity of the air-dried block permeated with strong groundwater was comparable(3.7×higher)to the hydraulic conductivity of the fresh block,indicating the self-healing of drying cracks after hydration and swelling in groundwater.A simplified method of protecting the block with plastic wraps before installation is recommended,since the remained swelling of the block hydrated in Beishan groundwater is sufficient to heal the drying cracks.
基金supported by the National Natural Science Foundation of China(51978133,52100026,U20A20322,52170151,51978132)the Fundamental Research Funds for the Central Universities of China(2412021QD022)+1 种基金the Key Research and Development Project of Hainan Province(ZDYF2022SHFZ298)the Industrialization Cultivation Project of Jilin Provincial Department of Education(JJKH20221174CY)。
文摘The occurrence of ultrafiltration(UF)membrane fouling frequently hampers the sustainable advancement of UF technology.Reactive self-cleaning UF membranes can effectively alleviate the problem of membrane fouling.Nevertheless,the self-cleaning process may accelerate membrane aging.Addressing these concerns,we present an innovative design concept for composite self-healing materials based on self-cleaning UF membranes.To begin,TiO_(2)nanoparticles were incorporated into the polymer molecular structure via molecular design,resulting in the synthesis of TiO_(2)/carboxyl-polyether sulfone(PES)hybrid materials.Subsequently,the nonsolvent-induced phase inversion technique was employed to prepare a novel of UF membrane.Lastly,a polyvinyl alcohol(PVA)hydrogel coating was applied to the hybrid UF membrane surface to create PVA@TiO_(2)/carboxyl-PES self-healing reactive UF membranes.By establishing a covalent bond,the TiO_(2)nanoparticles were effectively and uniformly dispersed within the UF membrane,leading to exceptional self-cleaning properties.Furthermore,the water-absorbing and swelling properties of PVA hydrogel,along with its capacity to form hydrogen bonds with water molecules,resulted in UF membranes with improved hydrophilicity and active self-healing abilities.The results demonstrated that the water contact angle of PVA@5%TiO_(2)/carboxyl-PES UF membrane was 43.1°.Following a 1-h exposure to simulated solar exposure,the water flux recovery ratio increased from 48.16%to 81.03%.Moreover,even after undergoing five cycles of 12-h simulated sunlight exposure,the UF membranes exhibited a consistent retention rate of over 97%,thus fully demonstrating their exceptional self-cleaning,antifouling,and selfhealing capabilities.We anticipate that the self-healing reactive UF membrane system will serve as a pioneering and comprehensive solution for the self-cleaning antifouling challenges encountered in UF membranes while also effectively mitigating the aging effects of reactive UF membranes.
基金the financial supports from the National Natural Science Foundation of China(52231007,51725101,11727807,22088101,52271167)the Shanghai Excellent Academic/Technological Leaders Program(19XD1400400)+4 种基金the Ministry of Science and Technology of China(973 Project Nos.2018YFA0209100 and 2021YFA1200600)the Fundamental Research Funds for the Central Universities(2022JCCXHH09)the Foundation for University Youth Key Teachers of Henan Province(2020GGJS170)the Support Program for Scientific and Technological Innovation Talents of Higher Education in Henan Province(21HASTIT004)Key Research Project of Zhejiang Lab(No.2021PE0AC02)。
文摘Hydrogels exhibit potential applications in smart wearable devices because of their exceptional sensitivity to various external stimuli.However,their applications are limited by challenges in terms of issues in biocompatibility,custom shape,and self-healing.Herein,a conductive,stretchable,adaptable,self-healing,and biocompatible liquid metal GaInSn/Ni-based composite hydrogel is developed by incorporating a magnetic liquid metal into the hydrogel framework through crosslinking polyvinyl alcohol(PVA)with sodium tetraborate.The excellent stretchability and fast self-healing capability of the PVA/liquid metal hydrogel are derived from its abundant hydrogen binding sites and liquid metal fusion.Significantly,owing to the magnetic constituent,the PVA/liquid metal hydrogel can be guided remotely using an external magnetic field to a specific position to repair the broken wires with no need for manual operation.The composite hydrogel also exhibits sensitive deformation responses and can be used as a strain sensor to monitor various body motions.Additionally,the multifunctional hydrogel displays absorption-dominated electromagnetic interference(EMI)shielding properties.The total shielding performance of the composite hydrogel increases to~62.5 dB from~31.8 dB of the pure PVA hydrogel at the thickness of 3.0 mm.The proposed bioinspired multifunctional magnetic hydrogel demonstrates substantial application potential in the field of intelligent wearable devices.
基金supported by China Postdoctoral Science Foundation(2022M710951,2022TQ0087)Postdoctoral Science Foundation of Heilongjiang Province(LBH-Z22111)。
文摘The booming wearable/portable electronic devices industry has stimulated the progress of supporting flexible energy storage devices.Excellent performance of flexible devices not only requires the component units of each device to maintain the original performance under external forces,but also demands the overall device to be flexible in response to external fields.However,flexible energy storage devices inevitably occur mechanical damages(extrusion,impact,vibration)/electrical damages(overcharge,over-discharge,external short circuit)during longterm complex deformation conditions,causing serious performance degradation and safety risks.Inspired by the healing phenomenon of nature,endowing energy storage devices with self-healing capability has become a promising strategy to effectively improve the durability and functionality of devices.Herein,this review systematically summarizes the latest progress in intrinsic self-healing chemistry for energy storage devices.Firstly,the main intrinsic self-healing mechanism is introduced.Then,the research situation of electrodes,electrolytes,artificial interface layers and integrated devices based on intrinsic self-healing and advanced characterization technology is reviewed.Finally,the current challenges and perspective are provided.We believe this critical review will contribute to the development of intrinsic self-healing chemistry in the flexible energy storage field.
文摘Today,self-healing graphene-and MXene-based composites have attracted researchers due to the increase in durability as well as the cost reduction in long-time applications.Different studies have focused on designing novel self-healing graphene-and MXenebased composites with enhanced sensitivity,stretchability,and flexibility as well as improved electrical conductivity,healing efficacy,mechanical properties,and energy conversion efficacy.These composites with self-healing properties can be employed in the field of wearable sensors,supercapacitors,anticorrosive coatings,electromagnetic interference shielding,electronic-skin,soft robotics,etc.However,it appears that more explorations are still needed to achieve composites with excellent arbitrary shape adaptability,suitable adhesiveness,ideal durability,high stretchability,immediate self-healing responsibility,and outstanding electromagnetic features.Besides,optimizing reaction/synthesis conditions and finding suitable strategies for functionalization/modification are crucial aspects that should be comprehensively investigated.MXenes and graphene exhibited superior electrochemical properties with abundant surface terminations and great surface area,which are important to evolve biomedical and sensing applications.However,flexibility and stretchability are important criteria that need to be improved for their future applications.Herein,the most recent advancements pertaining to the applications and properties of self-healing graphene-and MXene-based composites are deliberated,focusing on crucial challenges and future perspectives.
基金supported by the National Natural Science Foundation of China(51971040,52171101)the Natural Science Foundation of Chongqing(cstc2021jcyj-msxmX0613)+1 种基金the National Natural Science Foundation of China(52001036,51971044)the Independent Research Project of State Key Laboratory of Mechanical Transmissions(SKLMT-ZZKT-2022M12).
文摘Coating technologies are a commonly used way to protect metals against corrosion.However,with more and more severe service environments of materials,many protective coating systems often are not environmentally friendly or toxic as in the case of chromates.Based on the world’s abundant ideal magnesium(Mg)and its alloy,the smart self-healing anticorrosive coating can autonomously restore the damaged part of the coating according to the environmental changes,strengthen the corrosion protection ability,and prolong its service life.This paper reviews the research progress of smart self-healing coatings on Mg alloys.These coatings mostly contain suitable corrosion inhibitors encapsulated into micro/nano containers.Moreover,the different self-healing mechanisms and functionalities of micro/nano containers are discussed.The micro/nano containers range from inorganic nanocontainers such as mesoporous nanoparticles(silica(SiO_(2)),titanium dioxide(TiO_(2)),etc.),over inorganic clays(halloysite,hydrotalcite-like,zeolite),to organic nanocontainers such as polymer microcapsules,nanofibers,chitosan(CS)and cyclodextrin(CD),as well as,carbon materials such as graphene and carbon nanotubes and hybrids such as metal organic frameworks.The functioning of micro/nano containers can be divided in two principal groups:autonomous(based on defect filling and corrosion inhibition)and non-autonomous(based on dynamic bonds and shape memory polymers).Moreover,multi functionalities and composite applications of various micro/nano containers are summarized.At present,significant progress has been made in the preparation methods and technologies of micro/nano containers.Achieving long-term self-healing properties of coatings sensing of coating failure and early warning after self-healing function failure can be expected as the main development direction of self-healing corrosion protection coatings in the future.
基金supported by the National Natural Science Foundation of China(No.62274148),Science Foundation of Zhejiang Sci-Tech University(Nos.22062337-Y,20062224-Y,22062291-Y)Guangxi key laboratory of precision navigation technology and application[Guilin University of Electronic Technology](No.DH202229).
文摘Gallium oxide(Ga_(2)O_(3))based flexible heterojunction type deep ultraviolet(UV)photodetectors show excellent solar-blind photoelectric performance,even when not powered,which makes them ideal for use in intelligent wearable devices.How-ever,traditional flexible photodetectors are prone to damage during use due to poor toughness,which reduces the service life of these devices.Self-healing hydrogels have been demonstrated to have the ability to repair damage and their combination with Ga_(2)O_(3) could potentially improve the lifetime of the flexible photodetectors while maintaining their performance.Herein,a novel self-healing and self-powered flexible photodetector has been constructed onto the hydrogel substrate,which exhibits an excellent responsivity of 0.24 mA/W under 254 nm UV light at zero bias due to the built-in electric field originating from the PEDOT:PSS/Ga_(2)O_(3) heterojunction.The self-healing of the Ga_(2)O_(3) based photodetector was enabled by the reversible property of the synthesis of agarose and polyvinyl alcohol double network,which allows the photodetector to recover its original configu-ration and function after damage.After self-healing,the photocurrent of the photodetector decreases from 1.23 to 1.21μA,while the dark current rises from 0.95 to 0.97μA,with a barely unchanged of photoresponse speed.Such a remarkable recov-ery capability and the photodetector’s superior photoelectric performance not only significantly enhance a device lifespan but also present new possibilities to develop wearable and intelligent electronics in the future.
基金National Natural Science Foundation of China(52072297 and 51907149)Key R&D Plan of Shaanxi Province(2021GXLH-Z-068)+1 种基金China Postdoctoral Science Foundation(2019M653609)the Young Talent Support Plan of Xi’an Jiaotong University。
文摘The advance of microelectronics requires the micropower of microsupercapacitors(MSCs) to possess wide temperature-and damage-tolerance beyond high areal energy density.The properties of electrolyte are crucial for MSCs to meet the above requirements.Here,an organohydrogel electrolyte,featured with high salt tolerance,ultralow freezing point,and strong self-healing ability,is experimentally realized via modulating its inner dynamic bonds.Spectroscopic and theoretical analysis reveal that dimethyl sulfoxide has the ability to reconstruct Li^(+)solvation structure,and interact with free water and polyvinyl alcohol chains via forming hydrogen bonds.The organohydrogel electrolyte is employed to build MSCs,which show a boosted energy density,promising wide temperature range-and damage-tolerant ability.These attractive features make the designed organohydrogel electrolyte have great potential to advance MSCs.
基金support from National Natural Science Foundation of China(51873009)Beijing Natural Science Foundation(2192042).
文摘In this study,we proposed a self-healing conductive hydrogel based on polysaccharides and Li+to serve as flexible sensors.At first,the oxidized sodium alginate(OSA)was obtained through the oxidation reaction of sodium alginate(SA).Then OSA,carboxymethyl chitosan(CMC),and agarose(AGO)were dissolved in LiCl solution,respectively.Finally,the hydrogel was obtained through heating,mixing,and cooling processes.Because of the Schiff base structure and hydrogen bonding,the hydrogel demonstrates good mechanical and self-healing properties.The presence of Li+provides good conductivity for the hydrogel.In addition,we demonstrated the application of the hydrogel as the flexible sensors.It can perceive the process of pressing Morse code with the index finger as a pressure sensor and monitor sliding movement of the thumb as the strain sensor to browse the web with the mobile phone.Thus,the selfhealing conductive hydrogel may have potential applications in flexible wearable sensors.
文摘Magnesium(Mg) alloys are well-known in biomedical materials owing to their elastic module near to bone, biocompatibility and biodegradation properties. Nevertheless, poor corrosion resistance hinders their biomedical applications. Besides, it is necessary to endow Mg alloys with bioactive property, which is crucial for temporary bone implants. Here, a self-healing, corrosion resistant and bioactive duplex coating of plasma electrolytic oxidization(PEO)/polydopamine(PDA) is applied on AZ91 substrate using PEO and subsequent electrodeposition process. Moreover, the role of different electrodeposition times(60 s, 120 s) and dopamine concentrations(1 and 1.5 mg/ml) to improve corrosion resistance, bioactivity, biocompatibility and self-healing property and its mechanism are investigated. The results indicate that the PEO coating is efficiently sealed by the PDA, depending on the electrodeposition parameters. Noticeably, electrodeposition for 120 s in dopamine concentration of 1 mg/ml(120T-1C) results in the formation of uniform and crack-free PDA coating. Duplex PEO/PDA coatings reveal high bioactivity compared to PEO coating, owing to electrostatic interaction between PDA top-layer and calcium and phosphate ions as well as high hydrophilicity of coatings. In addition, duplex PEO/PDA coatings also show improved and more stable protective performance than the PEO and bare alloy, depending on the PDA deposition parameters. Noticeably, the corrosion current density of the 120T-1C decreases one orders of magnitude compared to PEO. In addition, the presence of a broad passivation region in the anodic polarization branch shows durable self-healing property via Zipper-like mechanism, demonstrating the duplex coating could preserve promising corrosion resistance.Furthermore, the cytocompatibility of duplex coated samples is also confirmed via interaction with MG63 cells. In summary, the PEO/PDA coating with great corrosion protection, self-healing ability, bioactivity and biocompatibility could be a promising candidate for degradable magnesium-based implants.
基金Funded by the Fundamental Research Funds for the Central Universities(No.2572021AW10)。
文摘In order to investigate the behavior characteristics of asphalt components during the process of nano-cracks temperature self-healing(NTS),molecular simulation technology was used to simulate the temperature self-healing of asphalt.Based on the determination of asphalts(virgin asphalt and aged asphalt),the proportional changes of asphalt components were confirmed.The distribution characteristics of asphalt components were obtained by marking different components in the process of NTS.At the same time,the rationality of the micro simulation findings was confirmed by asphalt performance tests and infrared spectroscopy results.The results show that different asphalt components have different behavior characteristics in the process of NTS.The content of asphaltene and resin plays a key role in the process of NTS,while saturation and aromatics play an active role in the temperature self-healing before and after aging.The NTS is the result of the comprehensive action of different components,and the self-healing efficiency is proportional to the relative molecular mass.The effect of aging on the NTS is also realized by changing the proportion of asphalt components.
基金supported by the National Key Research and Development Program of China (2017YFA0403803)the National Natural Science Foundation of China [Grant Nos.52022017,52074172,51974058,51927801]+1 种基金the Innovation Foundation of Science and Technology of Dalian [Grant No.2020RQ124]Fundamental Research Funds for the Central Universities。
文摘Bioinspired by Nepenthes, lubricant infused surfaces(LIS) have attracted widespread attention in the field of anticorrosion. However,the lubricant coating has some disadvantages such as complex construction processing and easy loss of oil phase in air or dynamic water phase. In this study, oleogel is infused into a lotus leaf inspired super-hydrophobic matrix to form an oleogel infused surface(OIS) for enhancing corrosion resistance of active Mg-Li alloy. For reserving oleogel, firstly, a facile one-step electrodeposition method is used to construct super-hydrophobic surface(SHS) composed by samarium/myristic acid complex micro-nano flower structure onto Mg-Li alloy.The coating exhibits excellent superhydrophobic property at a static contact angle of 160° by applying 30 V electrolysis for 30 min. The protection efficiency of single SHS highly relates with the metal itself. For short period immersion in water phase, SHS can afford protection to Mg-Li alloy. However, the long-term immersion will see the rapid failure of SHS, and the high activity of Mg-Li alloy is one main reason.We assume that SHS cannot be a good choice for protecting Mg-Li alloy. Then, a Nepenthes inspired liquid coating is formed by infusing oleogel into the micro-nano structure by a spin-coating method. The liquid coating performs prominent corrosion resistance with Rctreaching as high as 1.51 × 10^(10)Ω cm^(2). After the mechanical damage from the external environment, the liquid coating can realize self-repair through thermal assistance, and the liquid coating can still restore Rctup to 1.24 × 10^(10)Ω cm^(2) after healing. The corrosion resistance of the liquid coating remains strong by showing Rctas high as 1.14 × 10^(9)Ω cm^(2), even after immersion in representative corrosive 3.5 wt% Na Cl solution for 30 d.
基金supported by the National Natural Science Foundation of China(NSFC,Grant Nos.61874111,62174152 and 62022079)the National Key Research and Development Program of China(Grant No.2020YFB1506400)+1 种基金the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2020115)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA16021200).
文摘Ionic gels can be potentially used in wearable devices owing to their high humidity resistance and non-volatility.However,the applicability of existing ionic gel pressure sensors is limited by their low sensitivity.Therefore,it is very import-ant to develop an ionic gel pressure sensor with high sensitivity and a wide pressure detection range without sacrificing mechan-ical stretchability and self-healing ability.Herein,we report an effective strategy for developing pressure sensors based on ion-ic gel composites consisting of high-molecular-weight polymers,ionic liquids,and Au nanoparticles.The resulting capacitive pressure sensors exhibit high pressure sensitivity,fast response,and excellent self-healing properties.The sensors composed of highly hydrophobic polymers and ionic liquids can be used to track underwater movements,demonstrating broad application prospects in human motion state monitoring and underwater mechanical operations.
文摘Surface coatings have been extensively used to control the degradation rate of Mg alloys for bioimplant applications.However,these coatings only act as passive barriers.In corrosive media,structural damage impairs their barrier properties,resulting in rapid degradation of Mg alloys.The present study incorporates phytic acid(PA)as a healing agent in polycaprolactone(PCL)microcapsules with a unique honeycomb core matrix to obtain a self-healing PA-PCLcaps coating.The contact between simulated body fluid(SBF)and PA-PCLcaps coated ZM21 exhibited Cassie-Baxter interfacial states,resulting in significant hydrophobicity with a contact angle(CA)of 116.3.The corrosion potential(Ecorr)and current density(Icorr)were found to be-0.28 V and 1.1×10^(-9)A/cm^(2),respectively,for PA-PCLcaps coating,resulting in biosafe corrosion rate of 2.5×10^(-4)mm/year.After mechanical scratching,rapid HA mineralization at scratched regions recovered the hydrogen evolution rate(HER,0.36 mL/cm^(2)/day)and pH change(pH 7.10)of scratched PA-PCLcaps coated ZM21 samples to corresponding unscratched samples within one day of immersion.The coating’s self-healing ability could be attributed to PA released from punctured microcapsules,which facilitates HA chelation.The pH-triggered(pH 10)and Mg(II)-triggered(5 mM)conditions enhanced PA release from PA-PCLcaps coating by 2.5 and 3.1 times,respectively.As a result,dense HA mineralization occurred,which protects the coating from structural defects and ensures its durability in stimulating conditions.The findings of present study provide new insight for design of multiple stimuli-feedback based self-healing coatings on biodegradable Mg alloys.
