摘要
通过简便的湿化学方法,将Mn^(2+)离子掺杂到Cs_(2)ScCl_(5)·H_(2)O钙钛矿中,可以快速合成具有高光致发光量子产率的钙钛矿晶体.在红光区掺杂Mn^(2+)的钙钛矿晶体的量子产率比主体材料高出12倍以上,比CsMnCl_(3)·2H_(2)O高出近24倍.此外,利用密度泛函理论计算研究了材料的轨道杂化性质,进一步研究了材料的光学性质.Mn^(2+)掺杂后,被Sc八面体分离的Mn八面体可以更有效地限制激子,有利于提高量子产率.与原来的带隙相反,出现了归属于Mn和宿主元素的新杂化轨道.掺杂样品的吸收和激发范围从深紫外吸收扩展到紫外和可见吸收.基于上述性质,利用掺杂Mn^(2+)的钙钛矿制备了蓝芯片激发的高效白色发光二极管,其显色指数高达91,为未来在光电子领域的应用开辟了道路.
Perovskite crystals with high photoluminescence quantum yields can be rapidly synthesized by doping Mn^(2+)into Cs_(2)ScCl_(5)·H_(2)O through a facile wet chemistry approach.The quantum yield of the Mn^(2+)-doped perovskite crystals in the red light region is over 12 times higher than that of the host material and nearly 24 times higher than that of pure Mn based perovskite CsMnCl_(3)·2H_(2)O.Moreover,density functional theory calculations were used to study the orbital hybridization properties of the materials to further investigate their optical properties.After Mn^(2+)doping,the Mn octahedrons separated by the Sc octahedrons can more effectively restrict excitons,which is conducive to the improvement of quantum yields.Compared with the original band gap,a new hybridized orbital attributed to Mn and the host element appears.The doped sample shows an extended absorption and excitation range from the original deep-ultraviolet(UV)absorption to UV and visible absorption,Based on these properties,the Mn^(2+)-doped perovskites are used to prepare efficient white light-emitting diodes excited by a blue chip,showing an excellent color rendering index of 91,which meets the need for future applications in the field of optoelectronics.
作者
曹梦妍
李仁富
李智霖
赵修建
龚晓
Mengyan Cao;Renfu Li;Zhilin Li;Xiujian Zhao;Xiao Gong(State Key Laboratory of Silicate Materials for Architectures,Wuhan University of Technology,Wuhan 430070,China;Fujian Institute of Research on the Structure of Matter,Chinese Academy of Sciences,Fuzhou 350002,China)
基金
supported by the National Natural Science Foundation of China (21774098)
the “111” project (B18038)。
