Highly thermally conductive graphitic film(GF)materials have become a competitive solution for the thermal management of high-power electronic devices.However,their catastrophic structural failure under extreme altern...Highly thermally conductive graphitic film(GF)materials have become a competitive solution for the thermal management of high-power electronic devices.However,their catastrophic structural failure under extreme alternating thermal/cold shock poses a significant challenge to reliability and safety.Here,we present the first investigation into the structural failure mechanism of GF during cyclic liquid nitrogen shocks(LNS),which reveals a bubbling process characterized by“permeation-diffusion-deformation”phenomenon.To overcome this long-standing structural weakness,a novel metal-nanoarmor strategy is proposed to construct a Cu-modified graphitic film(GF@Cu)with seamless heterointerface.This well-designed interface ensures superior structural stability for GF@Cu after hundreds of LNS cycles from 77 to 300 K.Moreover,GF@Cu maintains high thermal conductivity up to 1088 W m^(−1)K^(−1)with degradation of less than 5%even after 150 LNS cycles,superior to that of pure GF(50%degradation).Our work not only offers an opportunity to improve the robustness of graphitic films by the rational structural design but also facilitates the applications of thermally conductive carbon-based materials for future extreme thermal management in complex aerospace electronics.展开更多
The synthesis of degradable polymers with easy-to-break in-chain carbon-oxygen bonds has attracted much attention.This minireview introduces the synthesis of a variety of degradable polymers from the(co)polymerization...The synthesis of degradable polymers with easy-to-break in-chain carbon-oxygen bonds has attracted much attention.This minireview introduces the synthesis of a variety of degradable polymers from the(co)polymerizations of several typical oxygenated monomers such as epoxides,cyclic carbonates,cyclic esters,carbon dioxide(CO_(2)),carbonyl sulfide(COS),and cyclic anhydrides.We highlight the catalysts and mechanisms for these(co)polymerizations.The ring-opening copolymerization of five-membered carbonate with cyclic anhydride or COS has been introduced.We also highlight the synthesis of block copolymers and cyclic copolymers with well-defined sequences by the method of growing center switching.We hope that these new polymerization systems can provide new ideas for the development of degradable low-carbon polymers in the future.展开更多
Pre-polymerized vinyl trimethoxy silane(PVTMS)@MWCNT nano-aerogel system was constructed via radical polymerization,sol-gel transition and supercritical CO_(2)drying.The fabricated organic-inorganic hybrid PVTMS@MWCNT...Pre-polymerized vinyl trimethoxy silane(PVTMS)@MWCNT nano-aerogel system was constructed via radical polymerization,sol-gel transition and supercritical CO_(2)drying.The fabricated organic-inorganic hybrid PVTMS@MWCNT aerogel structure shows nano-pore size(30-40 nm),high specific surface area(559 m^(2)g^(−1)),high void fraction(91.7%)and enhanced mechanical property:(1)the nano-pore size is beneficial for efficiently blocking thermal conduction and thermal convection via Knudsen effect(beneficial for infrared(IR)stealth);(2)the heterogeneous interface was beneficial for IR reflection(beneficial for IR stealth)and MWCNT polarization loss(beneficial for electromagnetic wave(EMW)attenuation);(3)the high void fraction was beneficial for enhancing thermal insulation(beneficial for IR stealth)and EMW impedance match(beneficial for EMW attenuation).Guided by the above theoretical design strategy,PVTMS@MWCNT nano-aerogel shows superior EMW absorption property(cover all Ku-band)and thermal IR stealth property(ΔT reached 60.7℃).Followed by a facial combination of the above nano-aerogel with graphene film of high electrical conductivity,an extremely high electromagnetic interference shielding material(66.5 dB,2.06 mm thickness)with superior absorption performance of an average absorption-to-reflection(A/R)coefficient ratio of 25.4 and a low reflection bandwidth of 4.1 GHz(A/R ratio more than 10)was experimentally obtained in this work.展开更多
Organic semiconductor single crystals(OSSCs) have shown their promising potential in high-performance organic field-effect transistors(OFETs). The interfacial dielectric layers are critical in these OFETs as they not ...Organic semiconductor single crystals(OSSCs) have shown their promising potential in high-performance organic field-effect transistors(OFETs). The interfacial dielectric layers are critical in these OFETs as they not only govern the key semiconductor/dielectric interface quality but also determine the growth of OSSCs by their wetting properties. However, reported interfacial dielectric layers either need rigorous preparation processes, rely on certain surface chemistry reactions, or exhibit poor solvent resistance, which limits their applications in low-cost, large-area, monolithic fabrication of OSSC-based OFETs. In this work, polyethylene(PE) thin films and lamellar single crystals are utilized as the interfacial dielectric layers, providing solvent resistive but wettable surfaces that facilitate the crystallization of 6,13-bis(tri-isopropylsilylethynyl)pentacene(TIPS-PEN) and 6,13-bis(triisopropylsilylethynyl)-5,7,12,14-tetraazapentacene(TIPS-TAP). As evidenced by the presence of ambipolar behavior in TIPS-PEN single crystals and the high electron mobility(2.3 ± 0.34 cm^(2)V^(-1)s^(-1)) in TIPS-TAP single crystals, a general improvement on electron transport with PE interfacial dielectric layers is revealed, which likely associates with the chemically inertness of the saturated C-H bonds. With the advantages in both processing and device operation, the PE interfacial dielectric layer potentially offers a monolithic way for the enhancement of electron transport in solution-processed OSSC-based OFETs.展开更多
The combinational density of immobilized functional molecules on biomaterial surfaces directs cell behaviors. However, limited by the low efficiency of traditional low-throughput experimental methods, investigation an...The combinational density of immobilized functional molecules on biomaterial surfaces directs cell behaviors. However, limited by the low efficiency of traditional low-throughput experimental methods, investigation and optimization of the combinational density remain daunting challenges. Herein, we report a high-throughput screening set-up to study biomaterial surface functionalization by integrating photo-controlled thiol-ene surface chemistry and machine learning-based label-free cell identification and statistics. Through such a strategy, a specific surface combinational density of polyethylene glycol (PEG) and arginine-glutamic acid-aspartic acid-valine peptide (REDV) leads to high endothelial cell (EC) selectivity against smooth muscle cell (SMC) was identified. The composition was translated as a coating formula to modify medical nickel-titanium alloy surfaces, which was then proved to improve EC competitiveness and induce endothelialization. This work provided a high-throughput method to investigate behaviors of co-cultured cells on biomaterial surfaces modified with combinatorial functional molecules.展开更多
Porous coatings with the features of muti-interfaces and high specific surface area have emerged as an excellent material platform for the manipulation of porous structures.Layer-by-layer(Lb L)assembly technique has b...Porous coatings with the features of muti-interfaces and high specific surface area have emerged as an excellent material platform for the manipulation of porous structures.Layer-by-layer(Lb L)assembly technique has been widely used in preparing porous polyelectrolyte coatings.However,the efficient construction of stable film from the Lb L technique is still a question.Herein,we reported a new solution to construct a stabilized polyelectrolyte coating with porous structures.Inspired by the mechanical reinforcement of double-network hydrogel,we constructed the poly(ethylenimine)(PEI)/poly(acrylic acid)(PAA)coating by in situ photopolymerization of acrylic acid in the PEI network instead of assembling PEI and PAA.Compared with the Lb L films,the in situ polymerized coating kept higher stability after 30 iterations of friction.Porous structures could also be constructed after acid treatment,which was utilized to load lubricant to enhance the lubricating property of the coating.This work provides a new method for the construction of dynamic and stable polyelectrolyte coatings,expediting more development of practical applications.展开更多
Organic field-effect transistors(OFETs)refer to field-effect transistors that use organic semiconductors as channel materials.Owing to the advantages of organic materials such as solution processability and intrinsic ...Organic field-effect transistors(OFETs)refer to field-effect transistors that use organic semiconductors as channel materials.Owing to the advantages of organic materials such as solution processability and intrinsic flexibility,OFETs are expected to be applicable in emergent technologies including wearable electronics and sensors,flexible displays,internet-of-things,neuromorphic computing,etc.Improving the electrical performance and developing multifunctionalities of OFETs are two major and closely relevant aspects for OFETs-related research.The former one aims for investigating the device physics and expanding the horizons of OFETs,while the later one is critical for leading OFETs into practical and emergent applications.The development in each of the two aspects would undoubtfully promote the other and bring more confidence for future development of OFETs.Hence,this review is divided into two parts that respectively summarize the recent progress in high-performance OFETs and multifunctional OFETs.展开更多
In this study,we report that Berlin Green(FeFe-BG)framework exhibits superior performance in the catalytic coupling of carbon disulfide(CS_(2))and propylene oxide(PO)to generate a random copolymer containing thioether...In this study,we report that Berlin Green(FeFe-BG)framework exhibits superior performance in the catalytic coupling of carbon disulfide(CS_(2))and propylene oxide(PO)to generate a random copolymer containing thioether,propylene monothiocarbonate and ether units.Oxygen and sulfur atom exchange was detected in polymeric and cyclic thiocarbonate byproducts and utilized to modulate the copolymerization of CS_(2)and propylene oxide.The coupling of PO and CS_(2)was selective for copolymer formation under various reaction conditions.^(1)H and^(13)C NMR spectroscopy determined two distinct polymer linkages and two cyclic byproducts.Copolymer number average molecular weights ranged from 6.4 kg/mol to 10.5 kg/mol,with a comparatively low polydispersity of 1.3-1.7.The CS_(2)/PO molar feed ratio had a significant impact on the O/S exchange process;the ratio of cyclic thiocarbonate byproducts could be efficiently regulated by tuning the CS_(2)molar feed ratio.展开更多
Comprehensive Summary In this work,we adopt a“heteroatom side-chains”modification strategy to modify the thiophene units in A-DA'D-A(acceptor-donor-acceptor’-donor-acceptor)type pentacyclic SMAs(small molecule ...Comprehensive Summary In this work,we adopt a“heteroatom side-chains”modification strategy to modify the thiophene units in A-DA'D-A(acceptor-donor-acceptor’-donor-acceptor)type pentacyclic SMAs(small molecule acceptors),that is,introducing branched alkyl chain at theβ-position of thiophene instead of straight alkyl chain,and then introducing oxygen atom at the third-position on the basis of branched chain.Two new pentacyclic SMAs(BZ4F-EH and BZ4F-OEH)were synthesized,and the influence of the heteroatom side-chains on photoelectric properties of A-DA'D-A type pentacyclic SMAs was systematically studied.Compared with our previously reported BZ4F(Y26),BZ4F-EH shows slightly blue-shifted absorption,while BZ4F-OEH has obvious red-shifted absorption.As a result,BZ4F-OEH-based binary device achieved a high power conversion efficiency(PCE)of 16.56%with a fill factor(FF)of 79.3%,which is the highest efficiency of pentacyclic SMAs to date.展开更多
Osteoarthritis(OA)is a prevalent chronic inflammatory disease in joints.Current interventions confront systemic toxicity and insufficient bioavailability.The unbalanced microenvironment of OA joints mainly fosters ove...Osteoarthritis(OA)is a prevalent chronic inflammatory disease in joints.Current interventions confront systemic toxicity and insufficient bioavailability.The unbalanced microenvironment of OA joints mainly fosters over-expressed reactive oxygen species(ROS),extracellular matrix disintegration,and apoptosis of chondrocytes.In this study,a kind of ROS-scavenging,biodegradable and drug-free nanoparticles(PP NPs)were constructed by the crosslinking of poly(propylene fumarate)(PPF)and ROS-scavenging poly(thioketal)(PTK).The high content of PTK and high crosslinking density of PPF and PTK innovatively endowed the NPs with slow degradation and prolonged ROS-elimination ability.The NPs were further surface-modified with chondroitin sulfate(CS),one of the dietary supplements for osteoarthritis.The intrinsic properties of resultant PP-CS NPs were excavated in vitro and in vivo.The PP-CS NPs could desirably consume 1,10-diphenyl-2-picrylhydrazyl(DPPH)radicals without toxicity to RAW264.7 cells in vitro.With an average diameter of~300 nm,the PP-CS NPs could be intra-articular administrated in OA rats and showed prolonged joint retention time,allowing only one injection per month.Moreover,the PP-CS NPs possessed a prolonged ROS depletion and M2 macrophage induction effect,down-regulated inflammatory cytokines,and reduced glycosaminoglycans loss.Consequently,the PP-CS NPs protected articular surface erosion,inhibited uneven cartilage matrix,and attenuated OA progression.展开更多
In 2022,The MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had achieved several important results.First,a series of well-defined dinuclear organoboron catalysts were develo...In 2022,The MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had achieved several important results.First,a series of well-defined dinuclear organoboron catalysts were developed to precisely control the enchainment of ether and carbonate segments during the copolymerization of CO_(2)and epoxides.Second,polyester had been synthesized through cationic copolymerization of cyclic anhydride.Third,ring-opening polymerization of carbon dioxide based valerolactone had been achieved,revealing the prospect of 3-ethylidene-6-vinyltetrahydro-2H-pyran-2-one(EVL)in utilizing CO_(2)and synthesizing functional polymers.Fourth,machine learning methods have been applied to biomaterial research,enabling high-throughput screening of functional biomaterial surfaces for implantable devices,and searching for potent antimicrobial peptides in whole combinatorial peptide libraries.Fifth,methods of characterization of biomacromolecule RNA transcription and manipulation of nucleoside modification were developed.Sixth,artificial enzymes-armed Bifidobacterium Longum probiotics were established to tune down gut inflammation.Seventh,three-dimensional(3D)printing technologies were used to engineer tough supramolecular hydrogels.Eighth,hydroplastic foaming graphene frameworks for acoustic and conductive polymer composites were provided for application.Ninth,aggregate photophysics about the nature of through-space interactions(TSIs)and manipulating their strength in small molecules with non-conjugated structure had been elucidated.Tenth,the forming mechanism of a newfound nested texture in poly(L-lactic acid)(PLLA)spherulitic films had been revealed.Finally,the isotropically dyeing mechanism of KDP single crystals grown from hydrogels have been explored.The related works are reviewed in this paper.展开更多
Toward future commercial applications of organic solar cells(OSCs),organic photovoltaic materials that enable high efficiency,excellent stability,and low cost should be developed.Fused-ring electron acceptors(FREAs)ha...Toward future commercial applications of organic solar cells(OSCs),organic photovoltaic materials that enable high efficiency,excellent stability,and low cost should be developed.Fused-ring electron acceptors(FREAs)have declared that OSCs are capable of showing efficiencies over 19%,whereas stability and cost are not solved yet.As the counterparts of FREAs,non-fused ring electron acceptors(NFREAs)are more flexible in molecular design.They have better stability because of the reduction of intramolecular tension via breaking fused backbone and have more advantages in cost with the reduction of synthetic complexity.However,the challenge for NFREAs is the relatively lower efficiencies(around 15%at current stage),which require better molecular designs for addressing the issues of conformational unicity and effective molecular packing.In this Account,we comprehensively summarize works about NFREAs carried out in our group from three main frameworks,including molecular design and efficiency optimization,material cost,and stability.First,in the part of molecular design and efficiency optimization,the existing rotatable single bond in NFREAs will bring the problem of conformational uncertainty,but it can be solved through proper molecular design,which also regulates the energy levels,light absorption range,and the packing mode of the molecule for obtaining higher performance.Thus,in this part,we discuss the evolution of NFREAs in three aspects,including molecular skeleton optimization,terminal modification,and side chain engineering.Many strategies are used in the design of a molecular skeleton,such as utilizing the quinoid effect,introducing functional groups with the electron push−pulling effect,and using multiple conformational lock.Furthermore,simplifying the skeleton is also the preferred development tendency.As for the terminal,the main modification strategy is adjusting the conjugation length and halogen atoms.What is more,by adjusting the side chain to induce appropriate steric hindrance,we can fix the orientation of molecules,thus regulating molecular packing modes.Second,regarding material cost,we compare the synthesis complexities between state-of-the-art FREAs and NFREAs.Because the synthesis processes of NFREAs reduce the complex cyclization reactions,the synthesis routes are greatly simplified,and the molecule can be obtained through three minimal steps.Third,regarding stability,we analyze the workable strategies used in NFREAs from the views of intrinsic material stability,photostability,and thermal stability.Finally,we conclude the challenges that should be conquered for NFREAs and propose perspectives that could be performed for NFREAs,with the hope of pushing the development of OSCs toward high performance,stability,and low cost.展开更多
One major remaining challenge in polymer chemistry is the development of efficient chemical recycling strategies to fully retrieve starting materials.Polytetrahydrofuran(PTHF)is widely used,but its stable ether bonds ...One major remaining challenge in polymer chemistry is the development of efficient chemical recycling strategies to fully retrieve starting materials.Polytetrahydrofuran(PTHF)is widely used,but its stable ether bonds make it difficult to chemically reuse after disposal.Here,we propose a“polymer A→polymer B”strategy for one-step quantitative upcycling of PTHF to polyesters.The route undergoes a cascade process:PTHF is depolymerized to give tetrahydrofuran(THF)that then alternately copolymerizes with cyclic anhydrides in situ,thereby pushing the chemical equilibrium of“PTHF⇌THF”to the right.The protocol demonstrates facile features:the use of common and metal-free Brønsted/Lewis acid as catalyst,a favorable reaction temperature of 100℃,and no use of solvents.This method also accommodates 18 cyclic anhydrides to give a library of polyesters with alternating sequences,tunable thermal properties,and high-fidelity carboxyl terminals.This is an unprecedented strategy for chemical recycling of waste polyether.展开更多
Graphene with linear energy dispersion and weak electron-phonon interaction is highly anticipated to harvest hot electrons in a broad wavelength range.However,the limited absorption and serious backscattering of hot-e...Graphene with linear energy dispersion and weak electron-phonon interaction is highly anticipated to harvest hot electrons in a broad wavelength range.However,the limited absorption and serious backscattering of hot-electrons result in inadequate quantum yields,especially in the mid-infrared range.Here,we report a macroscopic assembled graphene(nMAG)nanofilm/silicon heterojunction for ultrafast mid-infrared photodetection.The assembled Schottky diode works in 1.5-4.0μm at room temperature with fast response(20-30 ns,rising time,4 mm2 window)and high detectivity(1.61011 to 1.9109 Jones from 1.5 to 4.0μm)under the pulsed laser,outperforming single-layer-graphene/silicon photodetectors by 2-8 orders.These performances are attributed to the greatly enhanced photo-thermionic effect of electrons in nMAG due to its high light absorption(~40%),long carrier relaxation time(~20 ps),low work function(4.52 eV),and suppressed carrier number fluctuation.The nMAG provides a long-range platform to understand the hot-carrier dynamics in bulk 2D materials,leading to broadband and ultrafast MIR active imaging devices at room temperature.展开更多
基金the National Natural Science Foundation of China(Nos.52272046,52090030,52090031,52122301,51973191)the Natural Science Foundation of Zhejiang Province(LR23E020003)+4 种基金Shanxi-Zheda Institute of New Materials and Chemical Engineering(2021SZ-FR004,2022SZ-TD011,2022SZ-TD012,2022SZ-TD014)Hundred Talents Program of Zhejiang University(188020*194231701/113,112300+1944223R3/003,112300+1944223R3/004)the Fundamental Research Funds for the Central Universities(Nos.226-2023-00023,226-2023-00082,2021FZZX001-17,K20200060)National Key R&D Program of China(NO.2022YFA1205300,NO.2022YFA1205301,NO.2020YFF0204400,NO.2022YFF0609801)“Pioneer”and“Leading Goose”R&D Program of Zhejiang 2023C01190.
文摘Highly thermally conductive graphitic film(GF)materials have become a competitive solution for the thermal management of high-power electronic devices.However,their catastrophic structural failure under extreme alternating thermal/cold shock poses a significant challenge to reliability and safety.Here,we present the first investigation into the structural failure mechanism of GF during cyclic liquid nitrogen shocks(LNS),which reveals a bubbling process characterized by“permeation-diffusion-deformation”phenomenon.To overcome this long-standing structural weakness,a novel metal-nanoarmor strategy is proposed to construct a Cu-modified graphitic film(GF@Cu)with seamless heterointerface.This well-designed interface ensures superior structural stability for GF@Cu after hundreds of LNS cycles from 77 to 300 K.Moreover,GF@Cu maintains high thermal conductivity up to 1088 W m^(−1)K^(−1)with degradation of less than 5%even after 150 LNS cycles,superior to that of pure GF(50%degradation).Our work not only offers an opportunity to improve the robustness of graphitic films by the rational structural design but also facilitates the applications of thermally conductive carbon-based materials for future extreme thermal management in complex aerospace electronics.
基金the National Science Foundation of China(Nos.52203129,51973190)Zhejiang Provincial Department of Science and Technology(No.2020R52006).
文摘The synthesis of degradable polymers with easy-to-break in-chain carbon-oxygen bonds has attracted much attention.This minireview introduces the synthesis of a variety of degradable polymers from the(co)polymerizations of several typical oxygenated monomers such as epoxides,cyclic carbonates,cyclic esters,carbon dioxide(CO_(2)),carbonyl sulfide(COS),and cyclic anhydrides.We highlight the catalysts and mechanisms for these(co)polymerizations.The ring-opening copolymerization of five-membered carbonate with cyclic anhydride or COS has been introduced.We also highlight the synthesis of block copolymers and cyclic copolymers with well-defined sequences by the method of growing center switching.We hope that these new polymerization systems can provide new ideas for the development of degradable low-carbon polymers in the future.
基金the National Natural Science Foundation(No.52073187)NSAF Foundation(No.U2230202)for their financial support of this project+3 种基金National Natural Science Foundation(No.51721091)Programme of Introducing Talents of Discipline to Universities(No.B13040)State Key Laboratory of Polymer Materials Engineering(No.sklpme2022-2-03)support of China Scholarship Council
文摘Pre-polymerized vinyl trimethoxy silane(PVTMS)@MWCNT nano-aerogel system was constructed via radical polymerization,sol-gel transition and supercritical CO_(2)drying.The fabricated organic-inorganic hybrid PVTMS@MWCNT aerogel structure shows nano-pore size(30-40 nm),high specific surface area(559 m^(2)g^(−1)),high void fraction(91.7%)and enhanced mechanical property:(1)the nano-pore size is beneficial for efficiently blocking thermal conduction and thermal convection via Knudsen effect(beneficial for infrared(IR)stealth);(2)the heterogeneous interface was beneficial for IR reflection(beneficial for IR stealth)and MWCNT polarization loss(beneficial for electromagnetic wave(EMW)attenuation);(3)the high void fraction was beneficial for enhancing thermal insulation(beneficial for IR stealth)and EMW impedance match(beneficial for EMW attenuation).Guided by the above theoretical design strategy,PVTMS@MWCNT nano-aerogel shows superior EMW absorption property(cover all Ku-band)and thermal IR stealth property(ΔT reached 60.7℃).Followed by a facial combination of the above nano-aerogel with graphene film of high electrical conductivity,an extremely high electromagnetic interference shielding material(66.5 dB,2.06 mm thickness)with superior absorption performance of an average absorption-to-reflection(A/R)coefficient ratio of 25.4 and a low reflection bandwidth of 4.1 GHz(A/R ratio more than 10)was experimentally obtained in this work.
基金supported by the National Key Research and Development Program of China (Nos. 2019YFE0116700,2019YFA0705900) funded by MOSTNational Natural Science Foundation of China (Nos. 51873182, 52103231)+2 种基金Zhejiang Province Science and Technology Plan (No. 2021C04012) funded by Zhejiang Provincial Department of Science and TechnologyShanxiZheda Institute of Advanced Materials and Chemical Engineering(No. 2021SZ-FR003)the support by the Fundamental Research Funds for the Central Universities (No. 226-2023-00113)。
文摘Organic semiconductor single crystals(OSSCs) have shown their promising potential in high-performance organic field-effect transistors(OFETs). The interfacial dielectric layers are critical in these OFETs as they not only govern the key semiconductor/dielectric interface quality but also determine the growth of OSSCs by their wetting properties. However, reported interfacial dielectric layers either need rigorous preparation processes, rely on certain surface chemistry reactions, or exhibit poor solvent resistance, which limits their applications in low-cost, large-area, monolithic fabrication of OSSC-based OFETs. In this work, polyethylene(PE) thin films and lamellar single crystals are utilized as the interfacial dielectric layers, providing solvent resistive but wettable surfaces that facilitate the crystallization of 6,13-bis(tri-isopropylsilylethynyl)pentacene(TIPS-PEN) and 6,13-bis(triisopropylsilylethynyl)-5,7,12,14-tetraazapentacene(TIPS-TAP). As evidenced by the presence of ambipolar behavior in TIPS-PEN single crystals and the high electron mobility(2.3 ± 0.34 cm^(2)V^(-1)s^(-1)) in TIPS-TAP single crystals, a general improvement on electron transport with PE interfacial dielectric layers is revealed, which likely associates with the chemically inertness of the saturated C-H bonds. With the advantages in both processing and device operation, the PE interfacial dielectric layer potentially offers a monolithic way for the enhancement of electron transport in solution-processed OSSC-based OFETs.
基金supported by the National Key R&D Program of China(2022YFB3807300)the National Natural Science Foundation of China(52293381,22175152,52103188)+2 种基金the Joint Funds of the Zhejiang Provincial Natural Science Foundation of China and Huadong Medicine(LHDMZ22H300011)the Fundamental Research Funds for the Central Universities(226-2022-00146)the International Research Center for X Polymers,Zhejiang University(130000-171207723/001/010).
文摘The combinational density of immobilized functional molecules on biomaterial surfaces directs cell behaviors. However, limited by the low efficiency of traditional low-throughput experimental methods, investigation and optimization of the combinational density remain daunting challenges. Herein, we report a high-throughput screening set-up to study biomaterial surface functionalization by integrating photo-controlled thiol-ene surface chemistry and machine learning-based label-free cell identification and statistics. Through such a strategy, a specific surface combinational density of polyethylene glycol (PEG) and arginine-glutamic acid-aspartic acid-valine peptide (REDV) leads to high endothelial cell (EC) selectivity against smooth muscle cell (SMC) was identified. The composition was translated as a coating formula to modify medical nickel-titanium alloy surfaces, which was then proved to improve EC competitiveness and induce endothelialization. This work provided a high-throughput method to investigate behaviors of co-cultured cells on biomaterial surfaces modified with combinatorial functional molecules.
基金financially supported by the National Natural Science Foundation of China(No.U20A20262)Zhejiang Provincial Natural Science Foundation of China(No.LD22E030008)+1 种基金the Zhejiang Provincial Ten Thousand Talents Program(No.2018R52001)Fundamental Research Funds for the Central Universities(No.2021FZZX003-01-03)。
文摘Porous coatings with the features of muti-interfaces and high specific surface area have emerged as an excellent material platform for the manipulation of porous structures.Layer-by-layer(Lb L)assembly technique has been widely used in preparing porous polyelectrolyte coatings.However,the efficient construction of stable film from the Lb L technique is still a question.Herein,we reported a new solution to construct a stabilized polyelectrolyte coating with porous structures.Inspired by the mechanical reinforcement of double-network hydrogel,we constructed the poly(ethylenimine)(PEI)/poly(acrylic acid)(PAA)coating by in situ photopolymerization of acrylic acid in the PEI network instead of assembling PEI and PAA.Compared with the Lb L films,the in situ polymerized coating kept higher stability after 30 iterations of friction.Porous structures could also be constructed after acid treatment,which was utilized to load lubricant to enhance the lubricating property of the coating.This work provides a new method for the construction of dynamic and stable polyelectrolyte coatings,expediting more development of practical applications.
基金supported by the National Key Research and Development Program of China(Nos.2019YFE0116700 and 2019YFA0705900)Ministry of Science and Technology,National Natural Science Foundation of China(Nos.62075224,22021002,51873182 and 52103231)+3 种基金Zhejiang Province Science and Technology Plan(No.2021C04012)Zhejiang Provincial Department of Science and Technologysupported by the Lu Jiaxi International Teams Project(No.GJTD-2020–02)the Fundamental Research Funds for the Central Universities(No.2021QNA4033)。
文摘Organic field-effect transistors(OFETs)refer to field-effect transistors that use organic semiconductors as channel materials.Owing to the advantages of organic materials such as solution processability and intrinsic flexibility,OFETs are expected to be applicable in emergent technologies including wearable electronics and sensors,flexible displays,internet-of-things,neuromorphic computing,etc.Improving the electrical performance and developing multifunctionalities of OFETs are two major and closely relevant aspects for OFETs-related research.The former one aims for investigating the device physics and expanding the horizons of OFETs,while the later one is critical for leading OFETs into practical and emergent applications.The development in each of the two aspects would undoubtfully promote the other and bring more confidence for future development of OFETs.Hence,this review is divided into two parts that respectively summarize the recent progress in high-performance OFETs and multifunctional OFETs.
基金This work was supported by the National Natural Science Foundation of China(No.51973190)the Fund of Zhejiang Provincial Department of Science and Technology,China(Nos.2020R52006,2022C01216)the Fund of Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering,China(No.2021SZ-TD003).
文摘In this study,we report that Berlin Green(FeFe-BG)framework exhibits superior performance in the catalytic coupling of carbon disulfide(CS_(2))and propylene oxide(PO)to generate a random copolymer containing thioether,propylene monothiocarbonate and ether units.Oxygen and sulfur atom exchange was detected in polymeric and cyclic thiocarbonate byproducts and utilized to modulate the copolymerization of CS_(2)and propylene oxide.The coupling of PO and CS_(2)was selective for copolymer formation under various reaction conditions.^(1)H and^(13)C NMR spectroscopy determined two distinct polymer linkages and two cyclic byproducts.Copolymer number average molecular weights ranged from 6.4 kg/mol to 10.5 kg/mol,with a comparatively low polydispersity of 1.3-1.7.The CS_(2)/PO molar feed ratio had a significant impact on the O/S exchange process;the ratio of cyclic thiocarbonate byproducts could be efficiently regulated by tuning the CS_(2)molar feed ratio.
基金the National Natural Science Foundation of China(Nos.52125306,22005347,21875286)the Natural Science Foundation of Hunan Province(2021JJ20068)the Central South University Innovation-Driven Research Program(No.2023CXQD052).
文摘Comprehensive Summary In this work,we adopt a“heteroatom side-chains”modification strategy to modify the thiophene units in A-DA'D-A(acceptor-donor-acceptor’-donor-acceptor)type pentacyclic SMAs(small molecule acceptors),that is,introducing branched alkyl chain at theβ-position of thiophene instead of straight alkyl chain,and then introducing oxygen atom at the third-position on the basis of branched chain.Two new pentacyclic SMAs(BZ4F-EH and BZ4F-OEH)were synthesized,and the influence of the heteroatom side-chains on photoelectric properties of A-DA'D-A type pentacyclic SMAs was systematically studied.Compared with our previously reported BZ4F(Y26),BZ4F-EH shows slightly blue-shifted absorption,while BZ4F-OEH has obvious red-shifted absorption.As a result,BZ4F-OEH-based binary device achieved a high power conversion efficiency(PCE)of 16.56%with a fill factor(FF)of 79.3%,which is the highest efficiency of pentacyclic SMAs to date.
基金supported by the Key research and development program of Zhejiang Province(No.2021C03113)the Natural Science Foundation of Zhejiang Province(No.LD21E030001).
文摘Osteoarthritis(OA)is a prevalent chronic inflammatory disease in joints.Current interventions confront systemic toxicity and insufficient bioavailability.The unbalanced microenvironment of OA joints mainly fosters over-expressed reactive oxygen species(ROS),extracellular matrix disintegration,and apoptosis of chondrocytes.In this study,a kind of ROS-scavenging,biodegradable and drug-free nanoparticles(PP NPs)were constructed by the crosslinking of poly(propylene fumarate)(PPF)and ROS-scavenging poly(thioketal)(PTK).The high content of PTK and high crosslinking density of PPF and PTK innovatively endowed the NPs with slow degradation and prolonged ROS-elimination ability.The NPs were further surface-modified with chondroitin sulfate(CS),one of the dietary supplements for osteoarthritis.The intrinsic properties of resultant PP-CS NPs were excavated in vitro and in vivo.The PP-CS NPs could desirably consume 1,10-diphenyl-2-picrylhydrazyl(DPPH)radicals without toxicity to RAW264.7 cells in vitro.With an average diameter of~300 nm,the PP-CS NPs could be intra-articular administrated in OA rats and showed prolonged joint retention time,allowing only one injection per month.Moreover,the PP-CS NPs possessed a prolonged ROS depletion and M2 macrophage induction effect,down-regulated inflammatory cytokines,and reduced glycosaminoglycans loss.Consequently,the PP-CS NPs protected articular surface erosion,inhibited uneven cartilage matrix,and attenuated OA progression.
基金the support from the SCI-TECH Academy of Zhejiang University。
文摘In 2022,The MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had achieved several important results.First,a series of well-defined dinuclear organoboron catalysts were developed to precisely control the enchainment of ether and carbonate segments during the copolymerization of CO_(2)and epoxides.Second,polyester had been synthesized through cationic copolymerization of cyclic anhydride.Third,ring-opening polymerization of carbon dioxide based valerolactone had been achieved,revealing the prospect of 3-ethylidene-6-vinyltetrahydro-2H-pyran-2-one(EVL)in utilizing CO_(2)and synthesizing functional polymers.Fourth,machine learning methods have been applied to biomaterial research,enabling high-throughput screening of functional biomaterial surfaces for implantable devices,and searching for potent antimicrobial peptides in whole combinatorial peptide libraries.Fifth,methods of characterization of biomacromolecule RNA transcription and manipulation of nucleoside modification were developed.Sixth,artificial enzymes-armed Bifidobacterium Longum probiotics were established to tune down gut inflammation.Seventh,three-dimensional(3D)printing technologies were used to engineer tough supramolecular hydrogels.Eighth,hydroplastic foaming graphene frameworks for acoustic and conductive polymer composites were provided for application.Ninth,aggregate photophysics about the nature of through-space interactions(TSIs)and manipulating their strength in small molecules with non-conjugated structure had been elucidated.Tenth,the forming mechanism of a newfound nested texture in poly(L-lactic acid)(PLLA)spherulitic films had been revealed.Finally,the isotropically dyeing mechanism of KDP single crystals grown from hydrogels have been explored.The related works are reviewed in this paper.
基金supported by the National Natural Science Foundation of China(Grant No.5212780017,21734008,21875216,and 61721005)the S&T Innovation 2025 Major Special Program of Ningbo(No.2018B10055)the Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(2021SZ-FR001).
文摘Toward future commercial applications of organic solar cells(OSCs),organic photovoltaic materials that enable high efficiency,excellent stability,and low cost should be developed.Fused-ring electron acceptors(FREAs)have declared that OSCs are capable of showing efficiencies over 19%,whereas stability and cost are not solved yet.As the counterparts of FREAs,non-fused ring electron acceptors(NFREAs)are more flexible in molecular design.They have better stability because of the reduction of intramolecular tension via breaking fused backbone and have more advantages in cost with the reduction of synthetic complexity.However,the challenge for NFREAs is the relatively lower efficiencies(around 15%at current stage),which require better molecular designs for addressing the issues of conformational unicity and effective molecular packing.In this Account,we comprehensively summarize works about NFREAs carried out in our group from three main frameworks,including molecular design and efficiency optimization,material cost,and stability.First,in the part of molecular design and efficiency optimization,the existing rotatable single bond in NFREAs will bring the problem of conformational uncertainty,but it can be solved through proper molecular design,which also regulates the energy levels,light absorption range,and the packing mode of the molecule for obtaining higher performance.Thus,in this part,we discuss the evolution of NFREAs in three aspects,including molecular skeleton optimization,terminal modification,and side chain engineering.Many strategies are used in the design of a molecular skeleton,such as utilizing the quinoid effect,introducing functional groups with the electron push−pulling effect,and using multiple conformational lock.Furthermore,simplifying the skeleton is also the preferred development tendency.As for the terminal,the main modification strategy is adjusting the conjugation length and halogen atoms.What is more,by adjusting the side chain to induce appropriate steric hindrance,we can fix the orientation of molecules,thus regulating molecular packing modes.Second,regarding material cost,we compare the synthesis complexities between state-of-the-art FREAs and NFREAs.Because the synthesis processes of NFREAs reduce the complex cyclization reactions,the synthesis routes are greatly simplified,and the molecule can be obtained through three minimal steps.Third,regarding stability,we analyze the workable strategies used in NFREAs from the views of intrinsic material stability,photostability,and thermal stability.Finally,we conclude the challenges that should be conquered for NFREAs and propose perspectives that could be performed for NFREAs,with the hope of pushing the development of OSCs toward high performance,stability,and low cost.
基金support of the National Science Foundation of China(grant no.51973190)the Zhejiang Provincial Department of Science and Technology(grant no.2020R52006).
文摘One major remaining challenge in polymer chemistry is the development of efficient chemical recycling strategies to fully retrieve starting materials.Polytetrahydrofuran(PTHF)is widely used,but its stable ether bonds make it difficult to chemically reuse after disposal.Here,we propose a“polymer A→polymer B”strategy for one-step quantitative upcycling of PTHF to polyesters.The route undergoes a cascade process:PTHF is depolymerized to give tetrahydrofuran(THF)that then alternately copolymerizes with cyclic anhydrides in situ,thereby pushing the chemical equilibrium of“PTHF⇌THF”to the right.The protocol demonstrates facile features:the use of common and metal-free Brønsted/Lewis acid as catalyst,a favorable reaction temperature of 100℃,and no use of solvents.This method also accommodates 18 cyclic anhydrides to give a library of polyesters with alternating sequences,tunable thermal properties,and high-fidelity carboxyl terminals.This is an unprecedented strategy for chemical recycling of waste polyether.
基金National Natural Science Foundation of China,Grant/Award Numbers:52090030,51973191,92164106,61874094China Postdoctoral Science Foundation,Grant/Award Number:2020M681819+2 种基金Fundamental Research Funds for the Central Universities,Grant/Award Numbers:K20200060,2021FZZX001-17Key Laboratory of Novel Adsorption and Separation Materials and Application Technology of Zhejiang Province,Grant/Award Number:512301-I21502Hundred Talents Program of Zhejiang University,Grant/Award Number:188020*194231701/113。
文摘Graphene with linear energy dispersion and weak electron-phonon interaction is highly anticipated to harvest hot electrons in a broad wavelength range.However,the limited absorption and serious backscattering of hot-electrons result in inadequate quantum yields,especially in the mid-infrared range.Here,we report a macroscopic assembled graphene(nMAG)nanofilm/silicon heterojunction for ultrafast mid-infrared photodetection.The assembled Schottky diode works in 1.5-4.0μm at room temperature with fast response(20-30 ns,rising time,4 mm2 window)and high detectivity(1.61011 to 1.9109 Jones from 1.5 to 4.0μm)under the pulsed laser,outperforming single-layer-graphene/silicon photodetectors by 2-8 orders.These performances are attributed to the greatly enhanced photo-thermionic effect of electrons in nMAG due to its high light absorption(~40%),long carrier relaxation time(~20 ps),low work function(4.52 eV),and suppressed carrier number fluctuation.The nMAG provides a long-range platform to understand the hot-carrier dynamics in bulk 2D materials,leading to broadband and ultrafast MIR active imaging devices at room temperature.
