A new organic–inorganic ABX_(3)perovskite-type semiconducting hybrid,N-methylpyrrolidinium trichlorocadmate(MPCC),has been synthesized.It is found that MPCC exhibits semiconducting behaviour with an optical bandgap o...A new organic–inorganic ABX_(3)perovskite-type semiconducting hybrid,N-methylpyrrolidinium trichlorocadmate(MPCC),has been synthesized.It is found that MPCC exhibits semiconducting behaviour with an optical bandgap of∼4.65 eV,as well as remarkable dielectric switching properties.It displays a structural phase transition(SPT)at T_(c)=254 K,being confirmed by DSC and specific heat measurements.展开更多
Solid-state oxide ion and proton conductors are garnering significant attention due to their high ionic conductivity and potential applications in a range of electrochemical devices,including solid oxide fuel cells an...Solid-state oxide ion and proton conductors are garnering significant attention due to their high ionic conductivity and potential applications in a range of electrochemical devices,including solid oxide fuel cells and gas sensors.In this study,we report the influence of partial substitution of La^(3+)in isolated tetrahedral LaVO_(4)ceramics with 0.01 mol of alkaline-earth metals Ca^(2+),Sr^(2+)and Ba^(2+)on the phase stability and electrical properties.It was found that acceptor doping effectively enhances mixed oxide ion and proton conductivities,with Sr^(2+)substitution yielding the highest conductivity,achieving∼10^(−3)S cm^(−1)at 900℃under a wet O_(2)atmosphere.DFT calculations and ab initio molecular dynamics simulations revealed that protons preferentially form hydrogen bonds with the lattice oxygen near the dopants and migrate through a continuous process of hopping and rotation between inter-and intra-tetrahedral VO_(4)groups.Additionally,the existence of oxygen vacancies facilitates the formation of V_(2)O_(7)dimers through sharing corners with adjacent isolated VO4 tetrahedra,enabling ion exchange through a synergistic mechanism involving V2O7 dimer breaking and reforming.This research highlights the critical role of the deformation and rotational flexibility of isolated tetrahedral units in facilitating oxide ion and proton transport,underscoring the potential for developing mixed oxide ion and proton conductors in oxygen vacancy-deficient oxides with tetrahedral-based structures.展开更多
基金supported by the NSFC(21525104,21622108,21601188,91422301,21373220,51402296,21571178,51502288 and 51502290)the NSF for Distinguished Young Scholars of Fujian Province(2016J06012)+4 种基金the NSF of Fujian Province(2015J05040)the Strategic Priority Research Program of the CAS(XDB20000000)the Youth Innovation Promotion of CAS(2014262,2015240 and 2016274)the support from the“Chunmiao Projects”of Haixi Institute of CAS(CMZX-2014-003)Z.S.acknowledges the support from State Key Laboratory of Luminescence and Applications(SKLA-2016-09).
文摘A new organic–inorganic ABX_(3)perovskite-type semiconducting hybrid,N-methylpyrrolidinium trichlorocadmate(MPCC),has been synthesized.It is found that MPCC exhibits semiconducting behaviour with an optical bandgap of∼4.65 eV,as well as remarkable dielectric switching properties.It displays a structural phase transition(SPT)at T_(c)=254 K,being confirmed by DSC and specific heat measurements.
基金The National Natural Science Foundation of China(no.22365011,22005073,and 22090043)the Guangxi Natural Science Foundation(no.2020GXNSFAA297050 and 2019GXNSFBA245010)+2 种基金the EMERGIA program from Junta de Andalucía of Spain(2022/00001043)the Open Foundation of Key Laboratory of New Processing Technology for Nonferrous Metal&Materials,Ministry of Education/Guangxi Key Laboratory of Optical and Electronic Materials and Devices(22KF-1,20AA-1)the Scientific Research Start-up Fund of GLUT(GUTQDJJ 2017011)are acknowledged for the financial support.
文摘Solid-state oxide ion and proton conductors are garnering significant attention due to their high ionic conductivity and potential applications in a range of electrochemical devices,including solid oxide fuel cells and gas sensors.In this study,we report the influence of partial substitution of La^(3+)in isolated tetrahedral LaVO_(4)ceramics with 0.01 mol of alkaline-earth metals Ca^(2+),Sr^(2+)and Ba^(2+)on the phase stability and electrical properties.It was found that acceptor doping effectively enhances mixed oxide ion and proton conductivities,with Sr^(2+)substitution yielding the highest conductivity,achieving∼10^(−3)S cm^(−1)at 900℃under a wet O_(2)atmosphere.DFT calculations and ab initio molecular dynamics simulations revealed that protons preferentially form hydrogen bonds with the lattice oxygen near the dopants and migrate through a continuous process of hopping and rotation between inter-and intra-tetrahedral VO_(4)groups.Additionally,the existence of oxygen vacancies facilitates the formation of V_(2)O_(7)dimers through sharing corners with adjacent isolated VO4 tetrahedra,enabling ion exchange through a synergistic mechanism involving V2O7 dimer breaking and reforming.This research highlights the critical role of the deformation and rotational flexibility of isolated tetrahedral units in facilitating oxide ion and proton transport,underscoring the potential for developing mixed oxide ion and proton conductors in oxygen vacancy-deficient oxides with tetrahedral-based structures.
