The effects of yttrium(Y)and yttrium+calcium(Y+Ca)additions on the electrochemical properties and discharge performance of the as-extruded Mg−8Al−0.5Zn−0.2Mn(AZ80)anodes for Mg−air batteries were investigated.The resu...The effects of yttrium(Y)and yttrium+calcium(Y+Ca)additions on the electrochemical properties and discharge performance of the as-extruded Mg−8Al−0.5Zn−0.2Mn(AZ80)anodes for Mg−air batteries were investigated.The results show that the addition of 0.2 wt.%Y increased the corrosion resistance and discharge activity of AZ80 anode.This was attributed to the fine and sphericalβ-Mg_17)Al_(12) phases dispersing evenly in AZ80+0.2Y alloy,which suppressed the localized corrosion and severe“chunk effect”,and facilitated the rapid activation ofα-Mg.Combinative addition of 0.2 wt.%Y and 0.15 wt.%Ca generated grain refinement and a reduction of theβ-Mg_17)Al_(12) phase,resulting in a further enhancement in discharge voltage.However,the incorporation of Ca in Mg_17)Al_(12) and Al_(2)Y compounds compromised the corrosion resistance and anodic efficiency of AZ80+0.2Y+0.15Ca anode.Consequently,AZ80+0.2Y anode exhibited excellent overall discharge performance,with the peak discharge capacity and anodic efficiency of 1525 mA·h·g^(−1) and 67%at 80 mA/cm^(2),13%and 14%higher than those of AZ80 anode,respectively.展开更多
Thermal behavior of bulk amorphous sulfur is investigated by in situ temperature measurements at high pressures of 0.9, 1.4 and 2.1 GPa, and under different heating rates of 8, 10 and 12K/min at 0.9 GPa. The results s...Thermal behavior of bulk amorphous sulfur is investigated by in situ temperature measurements at high pressures of 0.9, 1.4 and 2.1 GPa, and under different heating rates of 8, 10 and 12K/min at 0.9 GPa. The results show that the onset temperature of the transition from the supercooled Hquid to the liquid state for sulfur increases with the pressure and the heating rate. It is deduced that the transition does not follow the Clapeyron equation, indicating considerable coupling of the molecular structure change in the transition. Along with the data at ambient pressure and high pressure, we present a dynamic diagram to demonstrate the relationship between the amorphous solid, supercooled liquid, liquid, and crystal phases of sulfur, and suggest an experimental approach to establish pressure-temperature-time transition diagrams for supercooled liquid and liquid.展开更多
Although the synthesis of novel nanostructured metal sulfides has been well established,further size-controllable optimization is still valuable to enhance their performance for various applications.Herein,a self-temp...Although the synthesis of novel nanostructured metal sulfides has been well established,further size-controllable optimization is still valuable to enhance their performance for various applications.Herein,a self-template method to size-controllably synthesize the hollow NiCo2S4 nanospheres is reported.Uniformly monodisperse Ni Co precursors with diameter widely ranging from 97 to 550 nm are controllably synthesized and subsequently transformed into hollow NiCo2S4 nanospheres through in situ sulfidation.Smaller nanoparticles’diameter results in the hollow NiCo2S4 nanospheres larger surface area and thinner shell thickness and hence provides much more electrochemical active sites as well as facilitate the ion and electron transfer.Consequently,the hollow NiCo2S4 nanospheres—used as the electrode materials in supercapacitors—achieve 19%enhancement of specific capacity from 484.8 to 575.1 C g-1 through lowering the 42.5%diameter of hollow NiCo2S4 nanospheres from 407 to 234 nm.Moreover,the hollow NiCo2S4 nanospheres with 234 nm diameter exhibit superior rate capacity indicated by 49%capacity retention from 1 to 50 A g-1 and excellent cycling stability(77%after 2000 cycles).Furthermore,this method is a potentially general strategy in the size-controllable synthesis of the metal sulfides hollow nanostructures and results in the remarkable electrochemical applications.展开更多
We investigate deformation and spallation of explosive welded bi-steel plates under gas gun shock loading.Free surface histories are measured to obtain the Hugoniot elastic limit and spall strengths at different impac...We investigate deformation and spallation of explosive welded bi-steel plates under gas gun shock loading.Free surface histories are measured to obtain the Hugoniot elastic limit and spall strengths at different impact velocities.Pre-and post-shock microstructures are characterized with optical metallography,scanning electron microscopy,and electron backscatter diffraction.In addition,the Vickers hardness test is conducted.Explosive welding can result in a wavy steel/steel interface,an ultrafine grain region centered at the interface,and a neighboring high deformation region,accompanied by a hardness with the highest value at the interface.Additional shock compression induces a further increase in hardness,and shock-induced deformation occurs in the form of twinning and dislocation slip and depends on the local substructure.Spall damage nucleates and propagates along the ultrafine grain region,due to the initial cracks or weak interface bonding.Spall strengths of bimetal plates can be higher than its constituents.Plate impact offers a promising method for improving explosive welding.展开更多
As a part of serial work about the application of a tetra-needle-shaped whisker(T-ZnOw) with a spatial structure in polymer composites,this work is focused on the effect of T-ZnOw dimension on the properties of polyme...As a part of serial work about the application of a tetra-needle-shaped whisker(T-ZnOw) with a spatial structure in polymer composites,this work is focused on the effect of T-ZnOw dimension on the properties of polymer composites. Two kinds of T-ZnOw whiskers with different dimensions(big and small one) are introduced into PA6 composites.Our results show that for the big whisker and the small whisker both,the addition of T-ZnOw induces the mechanical property improvement of T-ZnOw/PA6 composites.Especially,...展开更多
The main subject of this work is about the effect of T-ZnOw on the toughness and stiffness of polystyrene (PS).In order to avoid the rupture of T-ZnOw during the melt processing,T-ZnOw/PS composites were obtained via ...The main subject of this work is about the effect of T-ZnOw on the toughness and stiffness of polystyrene (PS).In order to avoid the rupture of T-ZnOw during the melt processing,T-ZnOw/PS composites were obtained via the combination of solution blending and injection moulding methods.Although the tensile strength of the composites decreases slightly,the impact strength and tensile modulus increase with the increase of the T-ZnOw content in the matrix.The stiffness and toughness of the composites are enhance...展开更多
The spraying-dried HA （ ASD ） was employed. ASD was plasma-sprayed onto ice to obtain hollow HA microspheres. The particle size of the sample was determined with a particle size analyzer. The morphology and structur...The spraying-dried HA （ ASD ） was employed. ASD was plasma-sprayed onto ice to obtain hollow HA microspheres. The particle size of the sample was determined with a particle size analyzer. The morphology and structure of the samples were measured by scanning electron microscope and X-ray powder diffraction. The in vitro biodegradability of samples was evaluated by immersion tests in Ringer＇ s solution （RS） and simulated body fluid （SBF）. The samples were immersed respectively in RS and SBF for a period. The Ca^2＋ ion concentration in the solutions was determined by Atomic Adsorption Spectrum. By plasma spraying hollow HA microspheres were obtained. The hollow microspheres consisted mainly of low crystalline and amorphous HA, and had better biodegradability.展开更多
Since Wigner et al. proposed that hydrogen would become metallic under sufficient pressure compres- sions in 1935,scientists have paid their attention on making metallic hydrogen at high pressures, and con- siderable ...Since Wigner et al. proposed that hydrogen would become metallic under sufficient pressure compres- sions in 1935,scientists have paid their attention on making metallic hydrogen at high pressures, and con- siderable progresses were made in theoretical and ex- perimental researches. Nellis et al. observed that the electrical resistivity of fluid hydrogen declined by several orders of magnitude when liquid hydrogen was multiply shocked to 140 GPa, and concluded that fluid hydrogen underwent metallization phase tran- sition from semiconductor to metal in their experi- ments. Although further researches should be carried out to distinguish the highly conductive state and the metallic state of fluid hydrogen, researchers have made great efforts to find new technical approaches to de- crease the threshold pressure for hydrogen metalliza- tion. For this purpose, hydrogen-rich compounds at- tract much attention. Some researchers believed that non-hydrogen elements in those compounds may re- duce, to some extent, the activation energy of met- allization by the effect of chemical pre-compression. Silane, a typical hydrogen-rich compound of group IV hydrides, has been the subject of most of the theoretical and experimental research so far, and it was also expected to be a potential candidate for a high-To superconductor at high pressure research.[61 Compared to hydrocarbons,[71 the chemical bonds in the silane molecule are theoretically more sensitive to pressure and temperature. At sufficiently high pres- sure and temperature, the fluid silane possibly be- comes some metallic alloy consisting of hydrogen and silicon elements. Theoretical calculations showed thatthe metallic transition for the silane system may oc- cur even below 100 GPa, while there are also some other later articles that claimed that silane would re- main an insulator up to around 200 GPa and became metallic and supconducting at 220 GPa with a theo- retical Tc of 16 K. Recently, Eremets et al. have re- ported that silane can transform to metal at 50 GPa, even to superconductor of Tc = 17K at 96GPa and 120GPa. The interesting question is whether tile Inetallization transition could occur under lower pres- sure by inulti-shock compression. Nellis et al. mea- sured the electrical conductivities of hydrocarbons shock-compressed to pressures from 20 GPa to 60 GPa, while for silane, experimental data of electrical resis- tivity under shock compression are scarce. In this Let- ter, the electrical resistivity of silane under nmltiply shock compression is obtained, and the experimental technique and data treatment are briefly described.展开更多
Two-dimensional(2D)layered materials,represented by graphene/graphene oxide(GO)and Ti_(3)C_(2)T_(x),are rapidly advancing in their application within anti-corrosion coatings.Their remarkable features,such as large spe...Two-dimensional(2D)layered materials,represented by graphene/graphene oxide(GO)and Ti_(3)C_(2)T_(x),are rapidly advancing in their application within anti-corrosion coatings.Their remarkable features,such as large specific surface area,adjustable structure and functionality,and diverse arrangement forms,endow them with vast potential as anticorrosion materials.This paper,anchored in the highly oriented arrangement of 2D materials in coatings,provides an overview of the anti-corrosion potential of composite materials with ordered microstructures.It explores the dispersion and orientation of 2D materials in resin coating matrices under force field induction,electric field induction,and magnetic field induction.Additionally,it offers a detailed introduction to recent advances in the self-aligned arrangement of graphene/graphene oxide and Ti_(3)C_(2)T_(x)in resin coatings,focusing on their anti-corrosion applications and underlying mechanisms.Finally,the paper summarizes and anticipates the future prospects of directional distribution of 2D materials in the anti-corrosion field,aiming to provide new insights into the interface construction and performance regulation of these materials,and to inspire the development of high-performance anti-corrosion coatings with simple preparation processes and exceptional protective properties.展开更多
Designing novel lubricants with easily customized structures,devisable compositions,and simple and economic synthesis over traditional lubricants is critical to fulfilling complex applications,prolonging machine lifet...Designing novel lubricants with easily customized structures,devisable compositions,and simple and economic synthesis over traditional lubricants is critical to fulfilling complex applications,prolonging machine lifetime,and saving energy.Deep eutectic solvents(DESs),which show tunable composition,adjustable structure,easy fabrication,and environmental friendliness,are promising candidates for variable and complicated lubricants applications.To promote the use of DESs as lubricants,a series of PEG200-based DESs with active heteroatoms were fabricated to tailor the tribological performance via tribo-chemistry.Thereinto,PEG200/boric acid(BA)DES shows optimal lubrication performance by forming tribo-chemical reaction film composited of B2O3,iron oxides,and FeOOH,and PEG200/thiourea(TU)DES displays abrasive wear-reducing property by producing FeS tribo-chemical film.Given the excellent abrasive wear-resistance of PEG200/TU DES and friction reduction of PEG200/BA DES,ternary PEG200/BA/TU DESs,composited of PEG200/TU DES and PEG200/BA DES,are first exploited.The ternary DESs possess superior wettability and thermal stability,which render them potential lubricants.Tribological tests of the ternary DESs demonstrate that synergistic lubrication is achieved by forming a transfer film consisting of FexBy,BN,B2O3,and FeS.Wherein FexBy,BN,and B2O3 increase load bearing of the film,and FeS mitigates severe abrasive wear.The proposed design philosophy of novel DESs as lubricants opens up a unique realm that is unattainable by traditional DESs lubrication mechanisms and provides a platform to design next-generation DESs lubrication systems.展开更多
In order to meet the requirements of the marine environment for microwave absorption(MA)materials,we put forward the strategy of constructing multi-functional composite materials,which integrate microwave absorption,a...In order to meet the requirements of the marine environment for microwave absorption(MA)materials,we put forward the strategy of constructing multi-functional composite materials,which integrate microwave absorption,anti-corrosion,and antibacterial properties.Herein,graphene oxide(GO)was used as a template to induce the growth of zeolitic imidazolate framework-8(ZIF-8),simultaneously as a two-dimensional(2D)nanocontainers to load corrosion inhibitors to achieve pH-responsive and self-healing properties.Finally,quaternary ammonium salt(dimethyl octadecyl(3-trimethoxylsilyl propyl)ammonium chloride(DMAOP))and sodium ascorbate(VCNa)were introduced to achieve synergistic antibacterial activity and the reduction of GO.The 2D strip-like structure of ZIF-8 was due to the confined growth induced by the electrostatic attraction between ZIF-8 and GO sheets.The as-obtained reduced GO(RGO)/ZIF-8/DMAOP5 exhibited excellent microwave absorption(MA)properties,with a minimum reflection loss(RL)value of-47.08 dB at 12.73 GHz when the thickness was 2.8 mm.Moreover,the effective absorption bandwidth reached 6.84 GHz.After soaking in 3.5%NaCl solution for 35 days,the RGO/ZIF-8/DMAOP5-0.7%coating still achieved an impedance value of 4.585×107Ω·cm^(2) and a protective efficiency of 99.994%,providing superior anti-corrosion properties.In addition,fantastic antibacterial activity was obtained,with the antibacterial rates of RGO/ZIF-8/DMAOP_(10) reaching 99.39%and 100%against Escherichia coli and Staphylococcus aureus.This work could open new avenues towards the development of a new generation of multifunctional MA materials.展开更多
Piezoelectric nanofibers have received extensive attention in the field of electronic devices,but they are still restricted for further development,due to their limited dipole arrangement.Herein,we propose spatially c...Piezoelectric nanofibers have received extensive attention in the field of electronic devices,but they are still restricted for further development,due to their limited dipole arrangement.Herein,we propose spatially confined MXene/polyvinylidene fluoride(PVDF)nanofibers for piezoelectric application,with dual functions of pressure sensing and energy harvesting.The spatial confinement of MXene/PVDF nanofibers can actively induce the optimally aligned-CH_(2)-/-CF_(2)-dipoles of PVDF and dramatically boost spontaneous polarization for piezoelectric enhancement.The voltage and current generated by fabricated MXene/PVDF(0.8 wt%)nanofiber piezoelectric electronic devices are respectively 3.97 times and 10.1 times higher than those generated by pure PVDF nanofibers.Based on these results,the developed bifunctional electronic devices are applied to monitor various human movements and to harvest energy.Notably,the results of this work allow for the development of nanofibers with excellent piezoelectric performance using a spatial confinement mechanism.展开更多
Respiration is a critical physiological process of the body and plays an essential role in maintaining human health.Wearable piezoelectric nanofiber-based respiratory monitoring has attracted much attention due to its...Respiration is a critical physiological process of the body and plays an essential role in maintaining human health.Wearable piezoelectric nanofiber-based respiratory monitoring has attracted much attention due to its self-power,high linearity,noninvasiveness,and convenience.However,the limited sensitivity of conventional piezoelectric nanofibers makes it difficult to meet medical and daily respiratory monitoring requirements due to their low electromechanical conversion efficiency.Here,we present a universally applicable,highly sensitive piezoelectric nanofiber characterized by a coaxial composite structure of polyvinylidene fluoride(PVDF)and carbon nanotube(CNT),which is denoted as PS-CC.Based on elucidating the enhancement mechanism from the percolation effect,PS-CC exhibits excellent sensing performance with a high sensitivity of 3.7 V/N and a fast response time of 20 ms for electromechanical conversion.As a proof-of-concept,the nanofiber membrane is seamlessly integrated into a facial mask,facilitating accurate recognition of respiratory states.With the assistance of a one-dimensional convolutional neural network(CNN),a PS-CC-based smart mask can recognize respiratory tracts and multiple breathing patterns with a classification accuracy of up to 97.8%.Notably,this work provides an effective strategy for monitoring respiratory diseases and offers widespread utility for daily health monitoring and clinical applications.展开更多
With the increasing demand for flexible piezoelectric sensor components,research on polyvinylidene fluoride(PVDF)based piezoelectric polymers is mounting up.However,the low dipole polarization and disordered polarizat...With the increasing demand for flexible piezoelectric sensor components,research on polyvinylidene fluoride(PVDF)based piezoelectric polymers is mounting up.However,the low dipole polarization and disordered polarization direction presented in PVDF hinder further improvement of piezoelectric properties.Here,we constructed an oriented tertiary structure,consisting of molecular chains,crystalline region,and MXene sheets,in MXene/PVDF nanocomposite via a temperature-pressure dual-field regulation method.The highly oriented PVDF molecular chains form approximately 90%of theβphase.In addition,the crystalline region structure with long-range orientation achieves out of plane polarization orientation.The parallel orientation arrangement of MXene effectively enhances the piezoelectric performances of the nanocomposite,and the current output of the device increases by nearly 23 times.This high output device is used to monitor exercise action,exploring the potential applications in wearable electronics.展开更多
As modern communication and detection technologies advance at a swift pace,multifunctional electromagnetic interference(EMI)shielding materials with active/positive infrared stealth,hydrophobicity,and electric-thermal...As modern communication and detection technologies advance at a swift pace,multifunctional electromagnetic interference(EMI)shielding materials with active/positive infrared stealth,hydrophobicity,and electric-thermal conversion ability have received extensive attention.Meeting the aforesaid requirements simultaneously remains a huge challenge.In this research,the melamine foam(MF)/polypyrrole(PPy)nanowire arrays(MF@PPy)were fabricated via one-step electrochemical polymerization.The hierarchical MF@PPy foam was composed of three-dimensional PPy micro-skeleton and ordered PPy nanowire arrays.Due to the upwardly grown PPy nanowire arrays,the MF@PPy foam possessed good hydrophobicity ability with a water contact angle of 142.00°and outstanding stability under various harsh environments.Meanwhile,the MF@PPy foam showed excellent thermal insulation property on account of the low thermal conductivity and elongated ligament characteristic of PPy nanowire arrays.Furthermore,taking advantage of the high conductivity(128.2 S m^(-1)),the MF@PPy foam exhibited rapid Joule heating under 3 V,resulting in dynamic infrared stealth and thermal camouflage effects.More importantly,the MF@PPy foam exhibited remarkable EMI shielding effectiveness values of 55.77 dB and 19,928.57 dB cm^(2)g^(-1).Strong EMI shielding was put down to the hierarchically porous PPy structure,which offered outstanding impedance matching,conduction loss,and multiple attenuations.This innovative approach provides significant insights to the development of advanced multifunctional EMI shielding foams by constructing PPy nanowire arrays,showing great applications in both military and civilian fields.展开更多
The lubrication performance of liquids is severely restricted and is degraded in high-temperature environments. Stable and reliable lubrication in high temperature environments has been a long-standing goal in various...The lubrication performance of liquids is severely restricted and is degraded in high-temperature environments. Stable and reliable lubrication in high temperature environments has been a long-standing goal in various industrial fields. In this study,WS_(2)and Ti_(3)C_(2)T_(x)MXene nanoflakes were used as oil-based lubricant additives to generate ultra-low friction and even superlubricity(friction coefficient of ~0.007) at elevated temperatures(400℃), which has hitherto not been achieved by both individual pristine materials, WS_(2)and Ti_(3)C_(2)T_(x)MXene. Viscosity and thermogravimetric characterization revealed improvements in the high-temperature rheological properties and thermal stability of the lubricating base oil, indicating improved loadbearing and continuous lubrication capabilities at elevated temperatures. X-ray photoelectron spectroscopy, transmission electron microscopy, and atomic force microscopy demonstrated that the formation of an iron/titanium/tungsten-rich oxide lubricious thin film at the sliding interface reduced the interfacial shear stress, which was responsible for the observed friction and wear reductions at high contact pressures(> 1.1 GPa). Although the titanium/tungsten oxide film was gradually removed after prolonged sliding, a sufficiently thick iron oxide film maintained a low friction coefficient for at least 2 h. The improved surface quality facilitates the achievement of ultra-low friction and reduced wear. The proposed lubrication methodology has a broad utilization potential as a wear-reduction strategy across various industrial fields at elevated temperatures.展开更多
The bonded MoS_(2)solid lubricant coating is an effective measure to mitigate the fretting wear of AISI 1045 steel.In this work,the amino functionalized MoS_(2)was protonated with acetic acid to make the MoS_(2)positi...The bonded MoS_(2)solid lubricant coating is an effective measure to mitigate the fretting wear of AISI 1045 steel.In this work,the amino functionalized MoS_(2)was protonated with acetic acid to make the MoS_(2)positively charged.The directional arrangement of protonated MoS2 in the coating was achieved by electrophoretic deposition under the electric field force.The bonded directionally aligned MoS_(2)solid lubricant coating showed high adaptability to various loads and excellent lubrication performance under all three working conditions.At a load of 10 N,the friction coefficient and wear volume of the coating with 5 wt%protonated MoS_(2)decreased by 20.0%and 37.2%compared to the pure epoxy coating,respectively,and by 0.07%and 16.8%than the randomly arranged MoS_(2)sample,respectively.The remarkable lubricating properties of MoS_(2)with directional alignment were attributed to its effective load-bearing and mechanical support,barrier effect on longitudinal extension of cracks,and the formation of a continuous and uniform transfer film.展开更多
Despite recent progress in the synthesis and application of graphene-based aerogels, some challenges such as scalable and cost-effective production, and miniaturization still remain, which hinder the practical applica...Despite recent progress in the synthesis and application of graphene-based aerogels, some challenges such as scalable and cost-effective production, and miniaturization still remain, which hinder the practical application of these materials. Here we report a large-scale electrospinning method to generate graphene-based aerogel microspheres （AMs）, which show broadband, tunable and high-performance microwave absorption. Graphene/Fe3O4 AMs with a large number of openings with hierarchical connecting radial microcharmels can be obtained via electrospinning-freeze drying followed by calcination. Importantly, for a given Fe3O4：graphene mass ratio, altering the shape of aerogel monoliths or powders into aerogel microspheres leads to unique electromagnetic wave properties. As expected, the reflection loss of graphene/Fe3O4 AMs-1：1 with only 5 wt.% absorber loading reaches -51.5 dB at 9.2 GHz with a thickness of 4.0 mm and a broad absorption bandwidth （RL 〈-10 dB） of 6.5 GHz. Furthermore, switching to coaxial electrospinning enables the fabrication of SiO2 coatings to construct graphene/Fe3O4@SiO2 core-shell AMs. The coatings influence the electromagnetic wave absorption of graphene/Fe3O4 AMs significantly. In view of these advantages, we believe that this processing technique may be extended to fabricate a wide range of unique graphene-based architectures for functional design and applications.展开更多
Although graphene aerogels(GA)have been attracted great attention,the easy-operation and large-scale production of GA are still challenges.Further,most GA have a monolith-like appearance,limiting their application-spe...Although graphene aerogels(GA)have been attracted great attention,the easy-operation and large-scale production of GA are still challenges.Further,most GA have a monolith-like appearance,limiting their application-specific needs.Herein,we highlight graphene aerogel spheres with controllable hollow structures(HGAS)that are delicately designed and manufactured via coaxial electrospinning coupled with freeze-drying and calcination.The HGAS exhibit a spherical configuration at the macroscale,while the construction elements of graphene on the microscale showing an interconnected radial microchannel structure.Further ball-in-ball graphene aerogel spheres(BGAS)are obtained by reference to the triaxial electrospinning technology.The as-prepared spheres possess the controllable integrated conductive networks,leading to the effective dielectric loss and impedance matching thus bringing on high-performance microwave absorption.The as-obtained HGAS shows a minimum reflection loss of-52.7 dB and a broad effective absorption bandwidth(f)of 7.0 GHz with thickness of 2.3 mm.Further,the fe reaches 9.3 GHz for BGAS with thickness of 3.4 mm.Aforementioned superior microwave absorption of HGAS and BGAS confirms combination of multiaxial electrospinning and freeze-drying on the multiscale is an effective strategy for scalable fabrication of advanced microwave.absorbing functional graphene aerogel spheres.展开更多
基金financial supports from the Key Development Project of Sichuan Province,China (No.2017GZ0399)the National Natural Science Foundation of China (No.52061040)the Open Projects of the Key Laboratory of Advanced Technologies of Materials,Ministry of Education,Southwest Jiaotong University,China (No.KLATM202003)。
文摘The effects of yttrium(Y)and yttrium+calcium(Y+Ca)additions on the electrochemical properties and discharge performance of the as-extruded Mg−8Al−0.5Zn−0.2Mn(AZ80)anodes for Mg−air batteries were investigated.The results show that the addition of 0.2 wt.%Y increased the corrosion resistance and discharge activity of AZ80 anode.This was attributed to the fine and sphericalβ-Mg_17)Al_(12) phases dispersing evenly in AZ80+0.2Y alloy,which suppressed the localized corrosion and severe“chunk effect”,and facilitated the rapid activation ofα-Mg.Combinative addition of 0.2 wt.%Y and 0.15 wt.%Ca generated grain refinement and a reduction of theβ-Mg_17)Al_(12) phase,resulting in a further enhancement in discharge voltage.However,the incorporation of Ca in Mg_17)Al_(12) and Al_(2)Y compounds compromised the corrosion resistance and anodic efficiency of AZ80+0.2Y+0.15Ca anode.Consequently,AZ80+0.2Y anode exhibited excellent overall discharge performance,with the peak discharge capacity and anodic efficiency of 1525 mA·h·g^(−1) and 67%at 80 mA/cm^(2),13%and 14%higher than those of AZ80 anode,respectively.
基金Supported by the National Natural Science Foundation of China under Grant No 11004163the Fundamental Research Funds for the Central Universities under Grant No 2682014ZT31
文摘Thermal behavior of bulk amorphous sulfur is investigated by in situ temperature measurements at high pressures of 0.9, 1.4 and 2.1 GPa, and under different heating rates of 8, 10 and 12K/min at 0.9 GPa. The results show that the onset temperature of the transition from the supercooled Hquid to the liquid state for sulfur increases with the pressure and the heating rate. It is deduced that the transition does not follow the Clapeyron equation, indicating considerable coupling of the molecular structure change in the transition. Along with the data at ambient pressure and high pressure, we present a dynamic diagram to demonstrate the relationship between the amorphous solid, supercooled liquid, liquid, and crystal phases of sulfur, and suggest an experimental approach to establish pressure-temperature-time transition diagrams for supercooled liquid and liquid.
基金supported by the National Natural Science Foundation of China(No.51602265)the Special Funding of China Postdoctoral Science Foundation(No.2018T110992)the Sichuan Science and Technology Program(No.2018RZ0074)
文摘Although the synthesis of novel nanostructured metal sulfides has been well established,further size-controllable optimization is still valuable to enhance their performance for various applications.Herein,a self-template method to size-controllably synthesize the hollow NiCo2S4 nanospheres is reported.Uniformly monodisperse Ni Co precursors with diameter widely ranging from 97 to 550 nm are controllably synthesized and subsequently transformed into hollow NiCo2S4 nanospheres through in situ sulfidation.Smaller nanoparticles’diameter results in the hollow NiCo2S4 nanospheres larger surface area and thinner shell thickness and hence provides much more electrochemical active sites as well as facilitate the ion and electron transfer.Consequently,the hollow NiCo2S4 nanospheres—used as the electrode materials in supercapacitors—achieve 19%enhancement of specific capacity from 484.8 to 575.1 C g-1 through lowering the 42.5%diameter of hollow NiCo2S4 nanospheres from 407 to 234 nm.Moreover,the hollow NiCo2S4 nanospheres with 234 nm diameter exhibit superior rate capacity indicated by 49%capacity retention from 1 to 50 A g-1 and excellent cycling stability(77%after 2000 cycles).Furthermore,this method is a potentially general strategy in the size-controllable synthesis of the metal sulfides hollow nanostructures and results in the remarkable electrochemical applications.
基金Supported by the National Basic Research Program of China under Grant No 2014CB845904the National Natural Science Foundation of China under Grant Nos 11627901,11372113 and 11672110
文摘We investigate deformation and spallation of explosive welded bi-steel plates under gas gun shock loading.Free surface histories are measured to obtain the Hugoniot elastic limit and spall strengths at different impact velocities.Pre-and post-shock microstructures are characterized with optical metallography,scanning electron microscopy,and electron backscatter diffraction.In addition,the Vickers hardness test is conducted.Explosive welding can result in a wavy steel/steel interface,an ultrafine grain region centered at the interface,and a neighboring high deformation region,accompanied by a hardness with the highest value at the interface.Additional shock compression induces a further increase in hardness,and shock-induced deformation occurs in the form of twinning and dislocation slip and depends on the local substructure.Spall damage nucleates and propagates along the ultrafine grain region,due to the initial cracks or weak interface bonding.Spall strengths of bimetal plates can be higher than its constituents.Plate impact offers a promising method for improving explosive welding.
基金supported by the National Natural Science Foundation of China(No50403019)Sichuan Youthful Science and Technology Foundation of China(No07ZQ026-003)
文摘As a part of serial work about the application of a tetra-needle-shaped whisker(T-ZnOw) with a spatial structure in polymer composites,this work is focused on the effect of T-ZnOw dimension on the properties of polymer composites. Two kinds of T-ZnOw whiskers with different dimensions(big and small one) are introduced into PA6 composites.Our results show that for the big whisker and the small whisker both,the addition of T-ZnOw induces the mechanical property improvement of T-ZnOw/PA6 composites.Especially,...
基金the National Natural Science Foundation of China (No.50403019)also partly supported by the Opening Project of State Key Laboratory of Polymer Materials Engineering (Sichuan University).
文摘The main subject of this work is about the effect of T-ZnOw on the toughness and stiffness of polystyrene (PS).In order to avoid the rupture of T-ZnOw during the melt processing,T-ZnOw/PS composites were obtained via the combination of solution blending and injection moulding methods.Although the tensile strength of the composites decreases slightly,the impact strength and tensile modulus increase with the increase of the T-ZnOw content in the matrix.The stiffness and toughness of the composites are enhance...
文摘The spraying-dried HA （ ASD ） was employed. ASD was plasma-sprayed onto ice to obtain hollow HA microspheres. The particle size of the sample was determined with a particle size analyzer. The morphology and structure of the samples were measured by scanning electron microscope and X-ray powder diffraction. The in vitro biodegradability of samples was evaluated by immersion tests in Ringer＇ s solution （RS） and simulated body fluid （SBF）. The samples were immersed respectively in RS and SBF for a period. The Ca^2＋ ion concentration in the solutions was determined by Atomic Adsorption Spectrum. By plasma spraying hollow HA microspheres were obtained. The hollow microspheres consisted mainly of low crystalline and amorphous HA, and had better biodegradability.
文摘Since Wigner et al. proposed that hydrogen would become metallic under sufficient pressure compres- sions in 1935,scientists have paid their attention on making metallic hydrogen at high pressures, and con- siderable progresses were made in theoretical and ex- perimental researches. Nellis et al. observed that the electrical resistivity of fluid hydrogen declined by several orders of magnitude when liquid hydrogen was multiply shocked to 140 GPa, and concluded that fluid hydrogen underwent metallization phase tran- sition from semiconductor to metal in their experi- ments. Although further researches should be carried out to distinguish the highly conductive state and the metallic state of fluid hydrogen, researchers have made great efforts to find new technical approaches to de- crease the threshold pressure for hydrogen metalliza- tion. For this purpose, hydrogen-rich compounds at- tract much attention. Some researchers believed that non-hydrogen elements in those compounds may re- duce, to some extent, the activation energy of met- allization by the effect of chemical pre-compression. Silane, a typical hydrogen-rich compound of group IV hydrides, has been the subject of most of the theoretical and experimental research so far, and it was also expected to be a potential candidate for a high-To superconductor at high pressure research.[61 Compared to hydrocarbons,[71 the chemical bonds in the silane molecule are theoretically more sensitive to pressure and temperature. At sufficiently high pres- sure and temperature, the fluid silane possibly be- comes some metallic alloy consisting of hydrogen and silicon elements. Theoretical calculations showed thatthe metallic transition for the silane system may oc- cur even below 100 GPa, while there are also some other later articles that claimed that silane would re- main an insulator up to around 200 GPa and became metallic and supconducting at 220 GPa with a theo- retical Tc of 16 K. Recently, Eremets et al. have re- ported that silane can transform to metal at 50 GPa, even to superconductor of Tc = 17K at 96GPa and 120GPa. The interesting question is whether tile Inetallization transition could occur under lower pres- sure by inulti-shock compression. Nellis et al. mea- sured the electrical conductivities of hydrocarbons shock-compressed to pressures from 20 GPa to 60 GPa, while for silane, experimental data of electrical resis- tivity under shock compression are scarce. In this Let- ter, the electrical resistivity of silane under nmltiply shock compression is obtained, and the experimental technique and data treatment are briefly described.
基金financial support provided by National Natural Science Foundation of China(U2141211,52201095)Sichuan Science Foundation for Distinguished Young Scholars(2023NSFSC1957)Fundamental Research Funds for the Central Universities(2682024GF006).
文摘Two-dimensional(2D)layered materials,represented by graphene/graphene oxide(GO)and Ti_(3)C_(2)T_(x),are rapidly advancing in their application within anti-corrosion coatings.Their remarkable features,such as large specific surface area,adjustable structure and functionality,and diverse arrangement forms,endow them with vast potential as anticorrosion materials.This paper,anchored in the highly oriented arrangement of 2D materials in coatings,provides an overview of the anti-corrosion potential of composite materials with ordered microstructures.It explores the dispersion and orientation of 2D materials in resin coating matrices under force field induction,electric field induction,and magnetic field induction.Additionally,it offers a detailed introduction to recent advances in the self-aligned arrangement of graphene/graphene oxide and Ti_(3)C_(2)T_(x)in resin coatings,focusing on their anti-corrosion applications and underlying mechanisms.Finally,the paper summarizes and anticipates the future prospects of directional distribution of 2D materials in the anti-corrosion field,aiming to provide new insights into the interface construction and performance regulation of these materials,and to inspire the development of high-performance anti-corrosion coatings with simple preparation processes and exceptional protective properties.
基金support from the National Natural Science Foundation of China(Nos.52175190 and 51805455)and the Fundamental Research Funds for the Central Universities(No.2682021CX117).
文摘Designing novel lubricants with easily customized structures,devisable compositions,and simple and economic synthesis over traditional lubricants is critical to fulfilling complex applications,prolonging machine lifetime,and saving energy.Deep eutectic solvents(DESs),which show tunable composition,adjustable structure,easy fabrication,and environmental friendliness,are promising candidates for variable and complicated lubricants applications.To promote the use of DESs as lubricants,a series of PEG200-based DESs with active heteroatoms were fabricated to tailor the tribological performance via tribo-chemistry.Thereinto,PEG200/boric acid(BA)DES shows optimal lubrication performance by forming tribo-chemical reaction film composited of B2O3,iron oxides,and FeOOH,and PEG200/thiourea(TU)DES displays abrasive wear-reducing property by producing FeS tribo-chemical film.Given the excellent abrasive wear-resistance of PEG200/TU DES and friction reduction of PEG200/BA DES,ternary PEG200/BA/TU DESs,composited of PEG200/TU DES and PEG200/BA DES,are first exploited.The ternary DESs possess superior wettability and thermal stability,which render them potential lubricants.Tribological tests of the ternary DESs demonstrate that synergistic lubrication is achieved by forming a transfer film consisting of FexBy,BN,B2O3,and FeS.Wherein FexBy,BN,and B2O3 increase load bearing of the film,and FeS mitigates severe abrasive wear.The proposed design philosophy of novel DESs as lubricants opens up a unique realm that is unattainable by traditional DESs lubrication mechanisms and provides a platform to design next-generation DESs lubrication systems.
基金supported by the National Natural Science Foundation of China(Nos.51903213 and 5217130190)the Science and Technology Planning Project of Sichuan Province(Nos.2023NSFSC1952 and 2022ZYD0028)+1 种基金the Central Government Guides Local Science and Technology Development Special Funds to freely explore basic research projects(No.2021Szvup124)the Fundamental Research Funds for the Central Universities(No.2682021GF004).
文摘In order to meet the requirements of the marine environment for microwave absorption(MA)materials,we put forward the strategy of constructing multi-functional composite materials,which integrate microwave absorption,anti-corrosion,and antibacterial properties.Herein,graphene oxide(GO)was used as a template to induce the growth of zeolitic imidazolate framework-8(ZIF-8),simultaneously as a two-dimensional(2D)nanocontainers to load corrosion inhibitors to achieve pH-responsive and self-healing properties.Finally,quaternary ammonium salt(dimethyl octadecyl(3-trimethoxylsilyl propyl)ammonium chloride(DMAOP))and sodium ascorbate(VCNa)were introduced to achieve synergistic antibacterial activity and the reduction of GO.The 2D strip-like structure of ZIF-8 was due to the confined growth induced by the electrostatic attraction between ZIF-8 and GO sheets.The as-obtained reduced GO(RGO)/ZIF-8/DMAOP5 exhibited excellent microwave absorption(MA)properties,with a minimum reflection loss(RL)value of-47.08 dB at 12.73 GHz when the thickness was 2.8 mm.Moreover,the effective absorption bandwidth reached 6.84 GHz.After soaking in 3.5%NaCl solution for 35 days,the RGO/ZIF-8/DMAOP5-0.7%coating still achieved an impedance value of 4.585×107Ω·cm^(2) and a protective efficiency of 99.994%,providing superior anti-corrosion properties.In addition,fantastic antibacterial activity was obtained,with the antibacterial rates of RGO/ZIF-8/DMAOP_(10) reaching 99.39%and 100%against Escherichia coli and Staphylococcus aureus.This work could open new avenues towards the development of a new generation of multifunctional MA materials.
基金supported by the Postdoctoral Innovation Talents Support Program(No.BX20220257)the Multiple Clean Energy Harvesting System(No.YYF20223026)+2 种基金the Sichuan Science and Technology Program(No.2023NSFSC0313)a Catalyst Seeding General Grant administered by the Royal Society of New Zealand(Contract 20-UOA-035-CSG)The authors are grateful for the help from the Analysis and Testing Center of Southwest Jiaotong University.
文摘Piezoelectric nanofibers have received extensive attention in the field of electronic devices,but they are still restricted for further development,due to their limited dipole arrangement.Herein,we propose spatially confined MXene/polyvinylidene fluoride(PVDF)nanofibers for piezoelectric application,with dual functions of pressure sensing and energy harvesting.The spatial confinement of MXene/PVDF nanofibers can actively induce the optimally aligned-CH_(2)-/-CF_(2)-dipoles of PVDF and dramatically boost spontaneous polarization for piezoelectric enhancement.The voltage and current generated by fabricated MXene/PVDF(0.8 wt%)nanofiber piezoelectric electronic devices are respectively 3.97 times and 10.1 times higher than those generated by pure PVDF nanofibers.Based on these results,the developed bifunctional electronic devices are applied to monitor various human movements and to harvest energy.Notably,the results of this work allow for the development of nanofibers with excellent piezoelectric performance using a spatial confinement mechanism.
基金supported by the Sichuan Science and Technology Program(No.2023NSFSC0313)the Basic Research Cultivation Project of Southwest Jiaotong University(No.2682023KJ024).
文摘Respiration is a critical physiological process of the body and plays an essential role in maintaining human health.Wearable piezoelectric nanofiber-based respiratory monitoring has attracted much attention due to its self-power,high linearity,noninvasiveness,and convenience.However,the limited sensitivity of conventional piezoelectric nanofibers makes it difficult to meet medical and daily respiratory monitoring requirements due to their low electromechanical conversion efficiency.Here,we present a universally applicable,highly sensitive piezoelectric nanofiber characterized by a coaxial composite structure of polyvinylidene fluoride(PVDF)and carbon nanotube(CNT),which is denoted as PS-CC.Based on elucidating the enhancement mechanism from the percolation effect,PS-CC exhibits excellent sensing performance with a high sensitivity of 3.7 V/N and a fast response time of 20 ms for electromechanical conversion.As a proof-of-concept,the nanofiber membrane is seamlessly integrated into a facial mask,facilitating accurate recognition of respiratory states.With the assistance of a one-dimensional convolutional neural network(CNN),a PS-CC-based smart mask can recognize respiratory tracts and multiple breathing patterns with a classification accuracy of up to 97.8%.Notably,this work provides an effective strategy for monitoring respiratory diseases and offers widespread utility for daily health monitoring and clinical applications.
基金the National Natural Science Foundation of China(No.52303328)the Postdoctoral Innovation Talents Support Program(No.BX20220257)+2 种基金the Multiple Clean Energy Harvesting System(No.YYF20223026)the Sichuan Science and Technology Program(No.2023NSFSC0313)a Catalyst Seeding General Grant administered by the Royal Society of New Zealand(Contract 20-UOA-035-CSG)。
文摘With the increasing demand for flexible piezoelectric sensor components,research on polyvinylidene fluoride(PVDF)based piezoelectric polymers is mounting up.However,the low dipole polarization and disordered polarization direction presented in PVDF hinder further improvement of piezoelectric properties.Here,we constructed an oriented tertiary structure,consisting of molecular chains,crystalline region,and MXene sheets,in MXene/PVDF nanocomposite via a temperature-pressure dual-field regulation method.The highly oriented PVDF molecular chains form approximately 90%of theβphase.In addition,the crystalline region structure with long-range orientation achieves out of plane polarization orientation.The parallel orientation arrangement of MXene effectively enhances the piezoelectric performances of the nanocomposite,and the current output of the device increases by nearly 23 times.This high output device is used to monitor exercise action,exploring the potential applications in wearable electronics.
基金supported by the Key Research and Development Program of Sichuan Province(Grant No.2023ZHCG0050)the Fundamental Research Funds for the Central Universities of China(Grant No.2682024QZ006 and 2682024ZTPY042)the Analytic and Testing Center of Southwest Jiaotong University.
文摘As modern communication and detection technologies advance at a swift pace,multifunctional electromagnetic interference(EMI)shielding materials with active/positive infrared stealth,hydrophobicity,and electric-thermal conversion ability have received extensive attention.Meeting the aforesaid requirements simultaneously remains a huge challenge.In this research,the melamine foam(MF)/polypyrrole(PPy)nanowire arrays(MF@PPy)were fabricated via one-step electrochemical polymerization.The hierarchical MF@PPy foam was composed of three-dimensional PPy micro-skeleton and ordered PPy nanowire arrays.Due to the upwardly grown PPy nanowire arrays,the MF@PPy foam possessed good hydrophobicity ability with a water contact angle of 142.00°and outstanding stability under various harsh environments.Meanwhile,the MF@PPy foam showed excellent thermal insulation property on account of the low thermal conductivity and elongated ligament characteristic of PPy nanowire arrays.Furthermore,taking advantage of the high conductivity(128.2 S m^(-1)),the MF@PPy foam exhibited rapid Joule heating under 3 V,resulting in dynamic infrared stealth and thermal camouflage effects.More importantly,the MF@PPy foam exhibited remarkable EMI shielding effectiveness values of 55.77 dB and 19,928.57 dB cm^(2)g^(-1).Strong EMI shielding was put down to the hierarchically porous PPy structure,which offered outstanding impedance matching,conduction loss,and multiple attenuations.This innovative approach provides significant insights to the development of advanced multifunctional EMI shielding foams by constructing PPy nanowire arrays,showing great applications in both military and civilian fields.
基金supported by the National Natural Science Foundation of China (Grant Nos. 52122507, 52350411, 52235004, and 52305214)the Sichuan Science and Technology Program (Grant Nos. 2023NSFSC1988, 2023YFSY0004)+1 种基金the Fundamental Research Funds for the Central Universities (Grant No. 2682021ZTPY095)the Independent Project of State Key Laboratory of Rail Transit Vehicle System (Grant No. 2023TPLT04)。
文摘The lubrication performance of liquids is severely restricted and is degraded in high-temperature environments. Stable and reliable lubrication in high temperature environments has been a long-standing goal in various industrial fields. In this study,WS_(2)and Ti_(3)C_(2)T_(x)MXene nanoflakes were used as oil-based lubricant additives to generate ultra-low friction and even superlubricity(friction coefficient of ~0.007) at elevated temperatures(400℃), which has hitherto not been achieved by both individual pristine materials, WS_(2)and Ti_(3)C_(2)T_(x)MXene. Viscosity and thermogravimetric characterization revealed improvements in the high-temperature rheological properties and thermal stability of the lubricating base oil, indicating improved loadbearing and continuous lubrication capabilities at elevated temperatures. X-ray photoelectron spectroscopy, transmission electron microscopy, and atomic force microscopy demonstrated that the formation of an iron/titanium/tungsten-rich oxide lubricious thin film at the sliding interface reduced the interfacial shear stress, which was responsible for the observed friction and wear reductions at high contact pressures(> 1.1 GPa). Although the titanium/tungsten oxide film was gradually removed after prolonged sliding, a sufficiently thick iron oxide film maintained a low friction coefficient for at least 2 h. The improved surface quality facilitates the achievement of ultra-low friction and reduced wear. The proposed lubrication methodology has a broad utilization potential as a wear-reduction strategy across various industrial fields at elevated temperatures.
基金the financial support of National Natural Science Foundation of China(Nos.52075458 and U2141211)Sichuan Science Foundation for Distinguished Young Scholars(No.2023NSFSC1957)the Analytical and Testing Center of Southwest Jiaotong University for support of the scanning electron microscopy(SEM)and Raman measurements.
文摘The bonded MoS_(2)solid lubricant coating is an effective measure to mitigate the fretting wear of AISI 1045 steel.In this work,the amino functionalized MoS_(2)was protonated with acetic acid to make the MoS_(2)positively charged.The directional arrangement of protonated MoS2 in the coating was achieved by electrophoretic deposition under the electric field force.The bonded directionally aligned MoS_(2)solid lubricant coating showed high adaptability to various loads and excellent lubrication performance under all three working conditions.At a load of 10 N,the friction coefficient and wear volume of the coating with 5 wt%protonated MoS_(2)decreased by 20.0%and 37.2%compared to the pure epoxy coating,respectively,and by 0.07%and 16.8%than the randomly arranged MoS_(2)sample,respectively.The remarkable lubricating properties of MoS_(2)with directional alignment were attributed to its effective load-bearing and mechanical support,barrier effect on longitudinal extension of cracks,and the formation of a continuous and uniform transfer film.
基金This work was financially supported by the National Natural Science Foundation of China （No. 51573149）, the Science and Technology Planning Project of Sichuan Province （No. 2016GZ0224）, the Fundamental Research Funds for the Central Universities （No. 2682016CX069） and the Student Research Training Program （No. 2017005）.
文摘Despite recent progress in the synthesis and application of graphene-based aerogels, some challenges such as scalable and cost-effective production, and miniaturization still remain, which hinder the practical application of these materials. Here we report a large-scale electrospinning method to generate graphene-based aerogel microspheres （AMs）, which show broadband, tunable and high-performance microwave absorption. Graphene/Fe3O4 AMs with a large number of openings with hierarchical connecting radial microcharmels can be obtained via electrospinning-freeze drying followed by calcination. Importantly, for a given Fe3O4：graphene mass ratio, altering the shape of aerogel monoliths or powders into aerogel microspheres leads to unique electromagnetic wave properties. As expected, the reflection loss of graphene/Fe3O4 AMs-1：1 with only 5 wt.% absorber loading reaches -51.5 dB at 9.2 GHz with a thickness of 4.0 mm and a broad absorption bandwidth （RL 〈-10 dB） of 6.5 GHz. Furthermore, switching to coaxial electrospinning enables the fabrication of SiO2 coatings to construct graphene/Fe3O4@SiO2 core-shell AMs. The coatings influence the electromagnetic wave absorption of graphene/Fe3O4 AMs significantly. In view of these advantages, we believe that this processing technique may be extended to fabricate a wide range of unique graphene-based architectures for functional design and applications.
基金This work was financially supported by the National Natural Science Foundation of China(No.51903213)the Science and Technology Planning Project of Sichuan Province(Nos.2018GZ0132 and 2018GZ0427).
文摘Although graphene aerogels(GA)have been attracted great attention,the easy-operation and large-scale production of GA are still challenges.Further,most GA have a monolith-like appearance,limiting their application-specific needs.Herein,we highlight graphene aerogel spheres with controllable hollow structures(HGAS)that are delicately designed and manufactured via coaxial electrospinning coupled with freeze-drying and calcination.The HGAS exhibit a spherical configuration at the macroscale,while the construction elements of graphene on the microscale showing an interconnected radial microchannel structure.Further ball-in-ball graphene aerogel spheres(BGAS)are obtained by reference to the triaxial electrospinning technology.The as-prepared spheres possess the controllable integrated conductive networks,leading to the effective dielectric loss and impedance matching thus bringing on high-performance microwave absorption.The as-obtained HGAS shows a minimum reflection loss of-52.7 dB and a broad effective absorption bandwidth(f)of 7.0 GHz with thickness of 2.3 mm.Further,the fe reaches 9.3 GHz for BGAS with thickness of 3.4 mm.Aforementioned superior microwave absorption of HGAS and BGAS confirms combination of multiaxial electrospinning and freeze-drying on the multiscale is an effective strategy for scalable fabrication of advanced microwave.absorbing functional graphene aerogel spheres.
