Homo- and Heterovalent Doping-Mediated Self-Trapped Exciton Emission and Energy Transfer in Mn-Doped Cs2Nal-xAgxBiCl6 Double Perovskites

作者:Ke, Bao; Zeng, Ruosheng*; Zhao, Zhuang; Wei, Qilin; Xue, Xiaogang; Bai, Kun; Cai, Chunxiao; Zhou, Weichang*; Xia, Zhiguo; Zou, Bingsuo*
来源:Journal of Physical Chemistry Letters, 2020, 11(1): 340-348.
DOI:10.1021/acs.jpclett.9b03387

摘要

Double perovskites exhibit low toxicity, intrinsic thermodynamic stability, and small carrier effective mass. Herein, a novel doping route was adopted to incorporate Mn ions into Cs2Na1-xAgxBiCl6 double perovskites for engineering the band gap and tailoring the energy transfer. The as-prepared Cs2Na1-xAgxBiCl6 (0 < x < 1) exhibited excellent photoluminescence and a broad self-trapped exciton (STE) band from 500 to 900 nm, which exhibited an abnormal emission peak blue shift with increasing temperature. For Mn-doped Cs2Na1-xAgxBiCl6, the two photoluminescence (PL) bands from d-d transition emission of Mn ions and STEs were always observed simultaneously in the PL The distinct energy-transfer channel from the Mn2+ ion guest to the double-perovskite host resulted in the dominant Mn2+ emission. Our results will be helpful for further understanding the nature of the photophysics of double perovskites.