Exploring the properties of lead-free hybrid double perovskites using a combined computational-experimental approach

TL;DR

This study combines computational screening and experimental synthesis to explore lead-free hybrid double perovskites, identifying promising candidates with suitable band gaps as alternatives to lead-based perovskites.

Contribution

It introduces a combined computational-experimental approach to identify and synthesize lead-free double perovskites with desirable electronic properties.

Findings

(MA)2TlBiBr6 has a band gap of ~2.0 eV.

Computational screening predicts suitable band gaps for certain compositions.

Successful synthesis confirms computational predictions.

Abstract

Density functional theory screening of the hybrid double perovskites (MA)2BIBiX6 (BI=K,Cu,Ag,Tl; X=Cl,Br,I) shows that systems with band gaps similar to those of the MAPbX3 lead compounds can be expected for BI=Cu,Ag,Tl. Motivated by these findings, (MA)2TlBiBr6, isoelectronic with MAPbBr3, was synthesised and found to have a band gap of ~2.0eV.