Acquiring high-performance and commercially available carbon based air-stable perovskite solar cells by using ZnBr2 additive

The organic-inorganic perovskite solar cells (PSCs) have recently attracted significant attention owing to their remarkable photovoltaic performance . Herein, we fabricate a novel perovskite absorber Cs 0.05 (FA 0.83 MA 0.17 ) 0.95 Pb 1−x Zn x (I 0.83 Br 0.17 ) 3 by using ZnBr 2 as an additive. The introduction of zinc increases the grain size and reduces the grain boundary defects. At the optimized concentration of 0.5 mol% ZnBr 2 additive, the x-ray diffraction (XRD) shows the perfect crystallization of the perovskite film. The enhanced crystallization of the perovskite structure suppresses the non-radiative recombination loss and prolongs the carrier lifetime. The optimized PSC presents a champion power conversion efficiency (PCE) of 15.64 % and shows a negligible hysteresis effect. Moreover, the increased built-in electric field (V bi ) between the n-type Zn doped perovskite and the p-type CuSCN creates more driving force for the separation of photogenerated carriers and increases the open-circuit photovoltage (V oc ) of the device. The unencapsulated device maintains more than 87 % of its original PCE after aging for 90 days in the ambient condition, while the control device can only maintain 60 % of its original PCE. These results suggest that the simple B-site ion-doped perovskite could be a good option for the future improvement of PSCs.