Bright luminescence of Sb doping in all-inorganic zinc halide perovskite variant

Halide lead perovskites are considered as one of the most promising optoelectronic materials in decades, but the toxicity and bio-accumulation of lead retard the commercialization. Therefore, seeking suitable lead-free perovskites and their variants are of vital importance. In this work, all-inorganic zinc halide perovskite variant Cs 2 ZnCl 4 crystals with Sb 3+ doping are synthesized via hydrothermal method . Transparent millimeter-sized crystals exhibit bright red photoluminescence (PL) under room temperature (RT) on account of self-trapped exciton (STE) emission of Sb 3+ , from 3 P 1 to 1 S 0 states. Temperature-dependent PL and time-resolved PL exhibit bimodality and intensity variations, revealing that Jahn-Teller effect of 3 P 1 state results two energy minima, and thermal activation may contribute to the spectrum change. Further, DFT calculations are carried out and the influences of Sb 3+ doping are revealed. A bandgap reduction is achieved via doping, and the band edges are localized at Sb 3+ . A combination of experimental and theoretical studies demonstrates well that the soft lattice structure and the 5s 2 lone pairs of Sb are vital for the STE emission.