Green-solvent-processed formamidinium-based perovskite solar cells with uniform grain growth and strengthened interfacial contact via a nanostructured tin oxide layer

-NRs/perovskite interface. More importantly, the photo and humidity stabilities of the unencapsulated device for up to 500 and 1000 hours are also achieved with negligible interfacial delamination after aging. This work provides a new perspective on the future industrial scale production of PSCs using environment-friendly solvents with compatible substrate design.