The ability to arbitrarily regulate semiconductor interfaces provides the most effective way to modulate the performance of optoelectronic devices. However, less work has been reported on piezo-modulated interface eng...The ability to arbitrarily regulate semiconductor interfaces provides the most effective way to modulate the performance of optoelectronic devices. However, less work has been reported on piezo-modulated interface engineering in all-oxide systems. In this paper, an enhanced photoresponse of an all-oxide Cu2O/ZnO heterojunction was obtained by taking advantage of the piezotronic effect. The illumination density-dependent piezoelectric modulation ability was also comprehensively investigated. An 18.6% enhancement of photoresponse was achieved when applying a a-0.88% compressive strain. Comparative experiments confirmed that this enhancement could be interpreted in terms of the band modification induced by interfacial piezoelectric polarization. The positive piezopotential generated at the ZnO side produces an increase in space charge region in Cu2O, thus providing an extra driving force to separate the excitons more efficiently under illumination. Our research provides a promising method to boost the performance of optoelectronics without altering the interface structure and could be extended to other metal oxide devices.展开更多
Global interest in lithium-sulfur batteries as one of the most promising energy storage technologies has been sparked by their low sulfur cathode cost,high gravimetric,volumetric energy densities,abundant resources,an...Global interest in lithium-sulfur batteries as one of the most promising energy storage technologies has been sparked by their low sulfur cathode cost,high gravimetric,volumetric energy densities,abundant resources,and environmental friendliness.However,their practical application is significantly impeded by several serious issues that arise at the cathode-electrolyte interface,such as interface structure degradation including the uneven deposition of Li_(2)S,unstable cathode-electrolyte interphase(CEI)layer and intermediate polysulfide shuttle effect.Thus,an optimized cathode-electrolyte interface along with optimized electrodes is required for overall improvement.Herein,we comprehensively outline the challenges and corresponding strategies,including electrolyte optimization to create a dense CEI layer,regulating the Li_(2)S deposition pattern,and inhibiting the shuttle effect with regard to the solid-liquid-solid pathway,the transformation from solid-liquid-solid to solid-solid pathway,and solid-solid pathway at the cathode-electrolyte interface.In order to spur more perceptive research and hasten the widespread use of lithium-sulfur batteries,viewpoints on designing a stable interface with a deep comprehension are also put forth.展开更多
A mechanical analysis is done to find the evolution of the interface profile between binary immiscible fluids induced by a three-dimensional orthogonal magnetic field gradient.In the experiments,the changes of the int...A mechanical analysis is done to find the evolution of the interface profile between binary immiscible fluids induced by a three-dimensional orthogonal magnetic field gradient.In the experiments,the changes of the interface profile between four groups of binary immiscible fluids are investigated under the same horizontal magnetic field gradients.The binary immiscible fluids are made of benzene and other liquids,like CuSO4,Fecl3,FeSO4 or Cucl2 aqueous solutions.In addition,the interface profile between the benzene and CuSO4 aqueous solution is examined under different horizontal magnetic field gradients.The experimental results are consistent with the theoretical analysis.This study explains the enhanced Moses effect from a mechanics standpoint.Furthermore,a new method for susceptibility measurement is proposed based on this enhanced Moses effect.展开更多
Chemically exfoliated nanosheets have exhibited great potential for applications in various electronic devices.Solution-based processing strategies such as inkjet printing provide a low-cost,environmentally friendly,a...Chemically exfoliated nanosheets have exhibited great potential for applications in various electronic devices.Solution-based processing strategies such as inkjet printing provide a low-cost,environmentally friendly,and scalable route for the fabrication of flexible devices based on functional inks of twodimensional nanosheets.In this study,chemically exfoliated high-k perovskite nanosheets(i.e.,Ca_(2)Nb_(3)O_(10)and Ca_(2)NaNb_(4)O_(13))are well dispersed in appropriate solvents to prepare printable inks,and then,a series of microcapacitors with Ag and graphene electrodes are printed.The resulting microcapacitors,Ag/Ca_(2)Nb_(3)O_(10)/Ag,graphene/Ca_(2)Nb_(3)O_(10)/graphene,and graphene/Ca_(2)NaNb_(4)O_(13)/graphene,demonstrate high capacitance densities of 20,80,and 150 nF/cm^(2) and high dielectric constants of 26,110.and 200,respectively.Such dielectric enhancement in the microcapacitors with graphene electrodes is possibly attributed to the dielectric/graphene interface.In addition,these microcapacitors also exhibit good insulating performance with a moderate electrical breakdown strength of approximately 1 MV/cm,excellent flexibility,and thermal stability up to 200℃.This work demonstrates the potential of high-k perovskite nanosheets for additive manufacturing of flexible high-performance dielectric capacitors.展开更多
基金Acknowledgements This work was supported by the National Major Research Program of China (2013CB932602), Major Project of International Cooperation and Exchanges (2012DFA50990), the Program of Introducing Talents of Discipline to Universities, National Natural Science Foundation of China (NSFC) (Nos. 51232001, 51172022, 51372023), the Research Fund of Co-construction Pro- gram from Beijing Municipal Commission of Education, the Fundamental Research Funds for the Central Universities, and the Program for Changjiang Scholars and Innovative Research Teams in Universitiesy.
文摘The ability to arbitrarily regulate semiconductor interfaces provides the most effective way to modulate the performance of optoelectronic devices. However, less work has been reported on piezo-modulated interface engineering in all-oxide systems. In this paper, an enhanced photoresponse of an all-oxide Cu2O/ZnO heterojunction was obtained by taking advantage of the piezotronic effect. The illumination density-dependent piezoelectric modulation ability was also comprehensively investigated. An 18.6% enhancement of photoresponse was achieved when applying a a-0.88% compressive strain. Comparative experiments confirmed that this enhancement could be interpreted in terms of the band modification induced by interfacial piezoelectric polarization. The positive piezopotential generated at the ZnO side produces an increase in space charge region in Cu2O, thus providing an extra driving force to separate the excitons more efficiently under illumination. Our research provides a promising method to boost the performance of optoelectronics without altering the interface structure and could be extended to other metal oxide devices.
基金supported by the National Natural Science Foundation of China(Grant Nos.52102302,22409161 and 52472249)the Young Talent Support Plan of Xi’an Jiaotong University(Grant No.DQ6J011)+4 种基金the Natural Science Foundation of Shaanxi Province(2023-JC-QN-0115)the China Postdoctoral Science Foundation(2022M712499)Beilin District Science and Technology Plan(GX2328)the support from Young Elite Scientists Sponsorship Program by Chinese Association for Science and Technologythe“High-Level Talent Introduction Plan”of Shaanxi Province and Siyuan Scholar of Xi’an Jiaotong University。
文摘Global interest in lithium-sulfur batteries as one of the most promising energy storage technologies has been sparked by their low sulfur cathode cost,high gravimetric,volumetric energy densities,abundant resources,and environmental friendliness.However,their practical application is significantly impeded by several serious issues that arise at the cathode-electrolyte interface,such as interface structure degradation including the uneven deposition of Li_(2)S,unstable cathode-electrolyte interphase(CEI)layer and intermediate polysulfide shuttle effect.Thus,an optimized cathode-electrolyte interface along with optimized electrodes is required for overall improvement.Herein,we comprehensively outline the challenges and corresponding strategies,including electrolyte optimization to create a dense CEI layer,regulating the Li_(2)S deposition pattern,and inhibiting the shuttle effect with regard to the solid-liquid-solid pathway,the transformation from solid-liquid-solid to solid-solid pathway,and solid-solid pathway at the cathode-electrolyte interface.In order to spur more perceptive research and hasten the widespread use of lithium-sulfur batteries,viewpoints on designing a stable interface with a deep comprehension are also put forth.
基金supported by the National Innovation Experimental Project for Undergraduate (Grant No. 070109)the Fundamental Research Fands for the central Universities (Grant No. 090209001)+1 种基金the Program for New Century Excellent Talents in University (Grant No. NCET-06-0289)the Programme of Introducing Talents of Discipline to Universities (GrantNo. B07015)
文摘A mechanical analysis is done to find the evolution of the interface profile between binary immiscible fluids induced by a three-dimensional orthogonal magnetic field gradient.In the experiments,the changes of the interface profile between four groups of binary immiscible fluids are investigated under the same horizontal magnetic field gradients.The binary immiscible fluids are made of benzene and other liquids,like CuSO4,Fecl3,FeSO4 or Cucl2 aqueous solutions.In addition,the interface profile between the benzene and CuSO4 aqueous solution is examined under different horizontal magnetic field gradients.The experimental results are consistent with the theoretical analysis.This study explains the enhanced Moses effect from a mechanics standpoint.Furthermore,a new method for susceptibility measurement is proposed based on this enhanced Moses effect.
基金supported by the Basic Science Center Program of National Natural Science Foundation of China(51788104)the National Natural Science Foundation of China(52172124 and51872214)the Fundamental Research Funds for the Central Universities(WUT:2021III019JC,2018III041GX)。
文摘Chemically exfoliated nanosheets have exhibited great potential for applications in various electronic devices.Solution-based processing strategies such as inkjet printing provide a low-cost,environmentally friendly,and scalable route for the fabrication of flexible devices based on functional inks of twodimensional nanosheets.In this study,chemically exfoliated high-k perovskite nanosheets(i.e.,Ca_(2)Nb_(3)O_(10)and Ca_(2)NaNb_(4)O_(13))are well dispersed in appropriate solvents to prepare printable inks,and then,a series of microcapacitors with Ag and graphene electrodes are printed.The resulting microcapacitors,Ag/Ca_(2)Nb_(3)O_(10)/Ag,graphene/Ca_(2)Nb_(3)O_(10)/graphene,and graphene/Ca_(2)NaNb_(4)O_(13)/graphene,demonstrate high capacitance densities of 20,80,and 150 nF/cm^(2) and high dielectric constants of 26,110.and 200,respectively.Such dielectric enhancement in the microcapacitors with graphene electrodes is possibly attributed to the dielectric/graphene interface.In addition,these microcapacitors also exhibit good insulating performance with a moderate electrical breakdown strength of approximately 1 MV/cm,excellent flexibility,and thermal stability up to 200℃.This work demonstrates the potential of high-k perovskite nanosheets for additive manufacturing of flexible high-performance dielectric capacitors.