p-Type Charge Transfer Doping of Graphene Oxide with (NiCo)1-yFeyOx for Air-Stable, All-Inorganic CsPbIBr2 Perovskite Solar Cells

The precise regulation of interfacial charge distribution highly determines the power conversion efficiency of perovskite solar cells (PSCs). Herein, inorganic (NiCo)(1-y)FeyOx nanoparticle decorated graphene oxide (GO) is successfully demonstrated as a hole booster for all-inorganic CsPbIBr2 PSC free of precious metal electrode. Arising from the spontaneous electron transfer induced p-type doping of GO from edged oxygen-containing functional groups to (NiCo)(1-y)FeyOx, the best all-inorganic CsPbIBr2 PSC achieves an efficiency of 10.95 % under one standard sun owing to the eliminated paradox between charge extraction and charge localization in GO surface. Furthermore, the champion device exhibits an excellent long-term stability at 10 % relative humidity without encapsulation over 70 days because of the suppressed ions migration.

Automated summary

By utilizing (NiCo)(1-y)FeyOx nanoparticle decorated graphene oxide (GO), the efficiency of all-inorganic CsPbIBr2 PSC was significantly improved, resolving the contradiction between charge extraction and localization. The top device exhibited excellent long-term stability under 10% relative humidity without encapsulation for over 70 days.