Fu Ruijing, Gao Junpeng, Wang Lingrui, Xiao Bin, Hu Tao, Wang Guangxia, Zeng Qingguang, Xiao Guanjun
School of Applied Physics and Materials, Wuyi University, Jiangmen 529020, P. R. China.
Institute of Carbon Peaking and Carbon Neutralization, Wuyi University, Jiangmen 529020, P. R. China.
Inorg Chem. 2024 Sep 30;63(39):18276-18284. doi: 10.1021/acs.inorgchem.4c03145. Epub 2024 Sep 19.
Optimizing the structure and tuning the optical properties in low-dimensional organic-inorganic halide perovskites are crucial to practical applications for stable solid-state lighting. Herein, we performed high-pressure investigations on one-dimensional (1D) postperovskite (TDMP)PbBr (TDMP = -2,5-dimethylpiperaziniium), and structure and optical properties under pressure are studied. (TDMP)PbBr exhibits color tunable emission from cool white light to yellow orange as the pressure increases from atmospheric pressure to 20.0 GPa. It was found that high pressure would facilitate trapping the free exciton (free exciton) to form a self-trapped exciton (STE) state due to increased electron-phonon interaction, thus enhancing STE emission in the pressure range of 4.0-7.0 GPa. At above 7.0 GPa, the STE emission is quenched, which is due to the phonon-assisted nonradiative relaxation. Meanwhile, (TDMP)PbBr displays reversible piezochromism from colorless to yellow under pressure as a result of the compound undergoing a reversible structural transformation. This work provides an insightful perspective on revealing the relationship between structure and optical properties of 1D postperovskites under high pressure.
优化低维有机-无机卤化物钙钛矿的结构并调节其光学性质对于稳定固态照明的实际应用至关重要。在此，我们对一维（1D）后钙钛矿（TDMP）PbBr（TDMP = -2,5-二甲基哌嗪鎓）进行了高压研究，并研究了压力下的结构和光学性质。随着压力从大气压增加到20.0 GPa，（TDMP）PbBr表现出从冷白光到黄橙色的颜色可调发射。研究发现，由于电子-声子相互作用增强，高压将促进捕获自由激子以形成自陷激子（STE）态，从而在4.0-7.0 GPa的压力范围内增强STE发射。在7.0 GPa以上，STE发射被淬灭，这是由于声子辅助的非辐射弛豫。同时，由于该化合物经历可逆的结构转变，（TDMP）PbBr在压力下表现出从无色到黄色的可逆压致变色。这项工作为揭示高压下一维后钙钛矿的结构与光学性质之间的关系提供了深刻的见解。
