Modified Transport-Layer Interfaces for Efficient and Hysteresis-free Planar-Perovskite Solar Cells

Hysteresis free p-i-n Perovskite solar cells are fabricated using NiO _x (p-type) and PCBM (n-type) as transport layers. The device's performance is improved by pre-conditioning both the NiOx/perovskite and perovskite/PCBM interfaces. NiO _x is exposed to ozone before perovskite deposition and that improves charge extraction and reduces device variability. PCBM/perovskite interface is improved by an ageing process after PCBM deposition that reduces hysteresis and improves charge-collection. Devices with modified interfaces and optimized perovskite thickness with improved lifetimes show 13.3% efficiency, 76% fill-factor and excellent device-to-device consistency.