摘要
全无机无铅钙钛矿Cs_(2)TiBr_(6)具有光电特性良好、带隙可调和环境友好等优点,是一种潜力巨大的光吸收材料。为改善Cs_(2)TiBr_(6)的相关性能,我们采用基于第一性原理的方法,针对Pd、Cl掺杂的Cs_(2)TiBr_(6)钙钛矿结构进行了研究。结果表明,用Pd取代Ti后产生杂质带,将原来间接带隙的Cs_(2)TiBr_(6)转变为直接带隙材料。用25.0%Pd掺杂后,晶体带隙值降低26%,掺杂后的晶体在320~415 nm近紫外光区吸收能力加强约50%,在645~900 nm的红外光区及近红外光区的光吸收能力加强约134%。在此基础上,将Cl与25.0%Pd共掺杂时,Cl掺杂不仅可以把Pd的形成能在单掺的基础上减小约9%,而且Cl的不同掺杂位置对材料的光电性能也有一定的影响。
The all-inorganic lead-free perovskite Cs_(2)TiBr_(6)has the advantages of good optoelectronic properties,adjustable bandgap,and environmental friendliness.It is a kind of light-absorbing material with great potential.To improve the related properties of Cs_(2)TiBr_(6),the first-principles-based method was used to study the structure of Pd and Cl doped Cs_(2)TiBr_(6)perovskite.The results show that the impurity band was generated after replacing Ti with Pd,which transforms the original indirect bandgap Cs_(2)TiBr_(6)into a direct bandgap material.After doping with 25.0%Pd,the bandgap value of the crystal was reduced by 26%,and the absorption capacity of the doped crystal in the nearultraviolet region of 320-415 nm was enhanced by about 50%.In the infrared and near-infrared regions of 645-900nm,the light absorption capacity was enhanced by about 134%.On this basis,when Cl was co-doped with 25.0%Pd,Cl doping can reduce the formation energy of Pd by about 9%based on single doping,and the position of Cl doping also affects the photoelectric properties of the material.
作者
王运运
张宇泽
韦建卫
曾晖
赵明
杨川
冯文林
马增威
WANG Yun-Yun;ZHANG Yu-Ze;WEI Jian-Wei;ZENG Hui;ZHAO Ming;YANG Chuan;FENG Wen-Lin;MA Zeng-Wei(Science of College,Chongqing University of Technology,Chongqing 400054,China;School of Electronic and Optical Engineering,Nanjing University of Science and Technology,Nanjing 210094,China)
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2022年第5期884-890,共7页
Chinese Journal of Inorganic Chemistry
基金
国家自然科学基金项目(No.51574054,61871227)
先进光电功能材料与器件重庆高校创新团队(No.CXTDX201601030)
重庆市科技创新领军人才(No.CSTCCXLJRC201905)资助。
关键词
钙钛矿
密度泛函理论
共掺杂
光电性能
perovskite
density functional theory
co-doping
optical properties
