La-Doped BaSnO${}_3$ Electron Transport Layer for Perovskite Solar Cells

Abstract

Due to the photo-instability and hysteresis of TiO${}_2$ electron transport layer (ETL) in perovskite solar cells (PSCs), novel electron transport materials are highly demanded. Here, we show ideal band alignment between La-doped BaSnO${}_3$ (LBSO) and methyl ammonium (MA) lead iodide perovskite (MAPbI${}_3$). The CH${}_3$NH${}_3$PbI${}_3$/La${}_x$Ba${}_{(1-x)}$SnO${}_3$ interface forms a stable all-perovskite heterostructure. The selective band alignment is manipulated with band gap renormalization by La-doping on the Ba site. LBSO shows high mobility, photo-stability, and structural stability, promising the next generation ETL materials.

4 pages, 4 figure