Cystamine-configured lead halide based 2D hybrid molecular crystals: Synthesis and photoluminescence systematics

Abstract

We have synthesized and studied a specific family of disulfide bridge based 2D organic inorganic hybrid perovskites using the cation, cystamine [2,2′-dithiobis(ethylammonium), abbreviated as SS] in the three lead halide (X = I, Br, and Cl) based systems, and explored their unique photo-physical properties. Green, blue, and white emissions are noted in I, Br, and Cl based systems, respectively. The experimental observations are compared with the results of first principles DFT calculations. The role of the halide ion (X) in the [Pb-X4] cages on the luminescence of the disulfide bridge based hybrid system is elucidated, and the corresponding systematics are analyzed.