Boosting the stability and efficiency of Cs2AgBiBr6 perovskite solar cells via Zn doping

Cesium silver bismuth halides(Cs 2 AgBiBr 6 ) perovskite solar cells(PSCs) exhibit low power conversion efficiency (PCE) due to their inherent defects. In this study, transition metal zinc(Zn) cation is firstly incorporated into Cs 2 AgBiBr 6 perovskites to form Cs 2( Ag 1-x Zn x) BiBr 6 , which significantly increases the efficiency of Cs 2 AgBiBr 6 -based perovskite solar cells by 45.9%, with an increase of 26.6% in short-circuit current density. Optoelectronic investigations demonstrate that the inclusion of Zn 2+ (10%)suppresses charge recombination, enhances electron extraction at the interface of TiO 2 /perovskite, and reduces trap density. Moreover, the stability against long-term environment and heat stress is maintained to nearly 90% of the initial PCE after aging in ambient atmosphere. This work emphasizes a useful strategy to boost the PCE of lead-free Cs 2 AgBiBr 6 -based perovskite solar cells and provides a new route for preparing high-performance and stable all-inorganic perovskite solar cell. • The Cs 2 (Ag 1-x Zn x) BiBr 6 perovskites were synthesized for the first time. • The power conversion efficiency of Cs 2 Ag 0.9 Zn 0.1 Br 6 -based solar cells is 2.16%. • The Cs 2 Ag 0.9 Zn 0.1 BiBr 6 owns the optimized stability. • The Cs 2 Ag 0.9 Zn 0.1 BiBr 6 possesses an excellent film quality.