The rapid consumption of fossil fuels has caused increasingly climatic issues and energy crisis,which leads to the urgent demand for developing sustainable and clean energies.Electrocatalysts play a key role in the de...The rapid consumption of fossil fuels has caused increasingly climatic issues and energy crisis,which leads to the urgent demand for developing sustainable and clean energies.Electrocatalysts play a key role in the development of electrochemical energy conversion and storage devices.Especially,developing efficient and cost-effective catalysts is important for the large-scale application of these devices.Among various electrocatalyst candidates,earth abundant transition metal compound(TMC)-based electrocatalysts are being widely and rapidly studied owing to their high electrocatalytic performances.This paper reviews the recent and representative advances in efficient TMC-based electrocatalysts(i.e.,oxides,sulfides,selenides,phosphides,carbides and nitrides)for energy electrocatalytic reactions,including hydrogen evolution reaction(HER),oxygen evolution reaction(OER)and oxygen reduction reaction(ORR).Different compounds with different applications are summarized and the relative mechanisms are also discussed.The strategies for developing earth-abundant and low-cost TMC-based electrocatalysts are introduced.In the end,the current challenges and future perspectives in the development of TMC research are briefly discussed.This review also provides the latest advance and outlines the frontiers in TMC-based electrocatalysts,which should provide inspirations for the further development of low-cost and high-efficiency catalysts for sustainable clean energy technologies.展开更多
Due to the coupling of piezoelectric and semiconducting dual properties,much attention has been focused on the piezoelectric semiconductor materials,such as ZnO,ZnS,CdS and GaN.With the usage of these piezoelectric se...Due to the coupling of piezoelectric and semiconducting dual properties,much attention has been focused on the piezoelectric semiconductor materials,such as ZnO,ZnS,CdS and GaN.With the usage of these piezoelectric semiconductor materials,novel nanodevices have been demonstrated,from which a new field called piezotronics was formulated.The core of piezotronics is to study the mechanism of the piezoelectric effect on tuning the charge transport behavior across various junctions or interfaces,with potential applications in sensors,microelectromechanical systems,and force/pressure triggered electric devices.Here following the theoretical frame work of piezotronic effect,analytical solutions of piezoelectric heterojunction are presented to investigate the electrical transport behavior at a p-n junction.Numerical simulation is given for guiding future experimental measurements.展开更多
High refractive index(HRI,n>1.8)photonic structures offer strong light confinement and refractive efficiencies,cover the entire visible spectrum and can be tuned by designing geometric arrayed features.However,its ...High refractive index(HRI,n>1.8)photonic structures offer strong light confinement and refractive efficiencies,cover the entire visible spectrum and can be tuned by designing geometric arrayed features.However,its practical applications are still hindered by the applicability and material limitation of lithography-based micro/nano fabrication approaches.Herein,we demonstrate a fluid-guided printing process for preparing HRI selenium microarrays.The microstructured flexible template is replicated from the diced silicon wafer without any lithography-based methods.When heated above the glass transition temperature,the flow characteristics of selenium endows the structure downsizing and orientation patterning between the target substrate and the template.Near 10 times narrowing selenium microarrays(1.9μm width)are patterned from the non-lithography template(18μm width).HRI selenium microarrays offer high refractive efficiencies and strong optical confinement abilities,which achieve angledependent structurally coloration and polarization.Meanwhile,the color difference can be recognized under the one degree distinction of the angle between incident and refracted light.This printing platform will facilitate HRI optical metasurfaces in a variety of applications,ranging from photonic sensor,polarization modulation to light manipulation.展开更多
基金supported by the National Natural Science Foundation of China(51804216 and 51972224)the Young Elite Scientists Sponsorship Program by CAST(2018QNRC001)+1 种基金Tianjin Natural Science Foundation(17JCQNJC02100)support from China Postdoctoral Science Foundation(2019M661014)。
文摘The rapid consumption of fossil fuels has caused increasingly climatic issues and energy crisis,which leads to the urgent demand for developing sustainable and clean energies.Electrocatalysts play a key role in the development of electrochemical energy conversion and storage devices.Especially,developing efficient and cost-effective catalysts is important for the large-scale application of these devices.Among various electrocatalyst candidates,earth abundant transition metal compound(TMC)-based electrocatalysts are being widely and rapidly studied owing to their high electrocatalytic performances.This paper reviews the recent and representative advances in efficient TMC-based electrocatalysts(i.e.,oxides,sulfides,selenides,phosphides,carbides and nitrides)for energy electrocatalytic reactions,including hydrogen evolution reaction(HER),oxygen evolution reaction(OER)and oxygen reduction reaction(ORR).Different compounds with different applications are summarized and the relative mechanisms are also discussed.The strategies for developing earth-abundant and low-cost TMC-based electrocatalysts are introduced.In the end,the current challenges and future perspectives in the development of TMC research are briefly discussed.This review also provides the latest advance and outlines the frontiers in TMC-based electrocatalysts,which should provide inspirations for the further development of low-cost and high-efficiency catalysts for sustainable clean energy technologies.
基金partly supported by the Beijing Institute of Nanoenergy and NanosystemsChinese Academy of Sciencesthe Fundamental Research Funds for the Central Universities(Grant No.Lzujbky-2013-35)
文摘Due to the coupling of piezoelectric and semiconducting dual properties,much attention has been focused on the piezoelectric semiconductor materials,such as ZnO,ZnS,CdS and GaN.With the usage of these piezoelectric semiconductor materials,novel nanodevices have been demonstrated,from which a new field called piezotronics was formulated.The core of piezotronics is to study the mechanism of the piezoelectric effect on tuning the charge transport behavior across various junctions or interfaces,with potential applications in sensors,microelectromechanical systems,and force/pressure triggered electric devices.Here following the theoretical frame work of piezotronic effect,analytical solutions of piezoelectric heterojunction are presented to investigate the electrical transport behavior at a p-n junction.Numerical simulation is given for guiding future experimental measurements.
基金the National Key R&D Program of China(2018YFA0208501)the National Natural Science Foundation of China(51803217,51773206,91963212,and 51961145102(BRICS Project))+3 种基金the Youth Innovation Promotion Association CAS(2020032)Beijing National Laboratory for Molecular Sciences(BNLMS-CXXM-202005)Russian Foundation for Basic Research(19-52-80036(BRICS Project))K.C.Wong Education Foundation。
文摘High refractive index(HRI,n>1.8)photonic structures offer strong light confinement and refractive efficiencies,cover the entire visible spectrum and can be tuned by designing geometric arrayed features.However,its practical applications are still hindered by the applicability and material limitation of lithography-based micro/nano fabrication approaches.Herein,we demonstrate a fluid-guided printing process for preparing HRI selenium microarrays.The microstructured flexible template is replicated from the diced silicon wafer without any lithography-based methods.When heated above the glass transition temperature,the flow characteristics of selenium endows the structure downsizing and orientation patterning between the target substrate and the template.Near 10 times narrowing selenium microarrays(1.9μm width)are patterned from the non-lithography template(18μm width).HRI selenium microarrays offer high refractive efficiencies and strong optical confinement abilities,which achieve angledependent structurally coloration and polarization.Meanwhile,the color difference can be recognized under the one degree distinction of the angle between incident and refracted light.This printing platform will facilitate HRI optical metasurfaces in a variety of applications,ranging from photonic sensor,polarization modulation to light manipulation.
