摘要
采用密度泛函理论研究了p型Na掺杂对Ca_2Co_2O_5基晶体材料电子状态的影响,并分析了内部微细电子结构.结果表明,纯的Ca_2Co_2O_5晶体材料和Na掺杂Ca_2Co_2O_5基晶体材料的能带均为各向异性的金属型能带.Na掺杂之后,在Ca_2Co_2O_5基晶体材料的费米面上插入了新的能级,多条简并态能级展开形成分立的能级.体系d态电子对Ca_2Co_2O_5基晶体材料费米面状态密度的贡献作用减弱,而p态电子对系统的贡献作用增强.p态和d态电子之间均存在着较强的相互作用,并且经过Na掺杂有增强的趋势.Na的掺杂造成Ca的电子数量减少导致其对态密度贡献程度降低,Ca—Co—O层中的Co和O的贡献程度均大大降低,Co—O层中的Co和O的贡献程度均大大提高.Na在掺杂Ca_2Co_2O_5基晶体材料中表现为弱的正离子中心,其对Ca位的掺杂属于p型掺杂.
The effects of ptype Na doping on electronic states of Ca2Co2O5 crystalline material and the corresponding detailed electronic structure have been studied by density functional theory.The results revealed that all systems are anisotropic metallic band structures,and new energy bands are inserted near Fermi level and several degenerated bands are displayed by Na doping for Ca.The contributions of dand pelectrons to system are decreased and enhanced,and there are strong interactions between pand delectrons,indicating that interaction can be enhanced by Na doping.The contributions of Ca electrons to system are decreased by Na doping as a result of the decreased electrons.The contributions of Co and O within the Ca—Co—O layer to system are decreased and the contributions of Co and O within the Co—O layer to system are much enhanced.The Na within the doped system exhibits weak cation character and the Na doping for Ca is ptype doping.
作者
张飞鹏
施加利
张静文
杜玲枝
张坤书
田中敏
杨新宇
张久兴
ZHANG Fei-peng;SHI Jia-li;ZHANG Jing-wen;DU Ling-zhi;ZHANG Kun-shu;TIAN Zhong-min;YANG Xin-yu;ZHANG Jiu-xing(Henan Provincial Engineering Laboratory of Building-Photovoltaics,Institute of Sciences,Henan University of Urban Construction,Pingdingshan 467036,China;School of Materials Sciences and Engineering,Shijiazhuang Tiedao University,Shijiazhuang 050043,China;Anhui Provincial Key Laboratory of Advanced Functional Materials and Devices,College of Materials Science and Engineering,Hefei University of Technology,Hefei 230009,China)
出处
《分子科学学报》
CAS
北大核心
2019年第2期102-109,共8页
Journal of Molecular Science
基金
国家自然科学基金资助项目(51572066)
河南省自然科学基金面上项目(162300410007)
河南省科技计划项目(132300410071)
