Synthesis and Properties of a Lead-Free Hybrid Double Perovskite: (CH3NH3)2AgBiBr6 

Fengxia Wei, Zeyu Deng, Shijing Sun, Fenghua Zhang, Donald M. Evans, Gregor Kieslich, Satoshi Tominaka, Michael A. Carpenter, Jie Zhang, Paul D. Bristowe and Anthony K. Cheetham

6th of January 2017

Abstract

The discovery of lead-free hybrid double perovskites provides a viable approach in the search for stable and environmentally benign photovoltaic materials as alternatives to lead-containing systems such as MAPbX3 (X = Cl, Br, or I). Following our recent reports of (MA)2KBiCl6 and (MA)2TlBiBr6, we have now synthesized a hybrid double perovskite, (MA)2AgBiBr6, that has a low band gap of 2.02 eV and is relatively stable and nontoxic. Its electronic structure and mechanical and optical properties are investigated with a combination of experimental studies and density functional theory calculations.