Low-Temperature synthesis of FeOOH Quantum Dots as Promising Electron-Transporting Layers for High-Performance Planar Perovskite Solar Cells

The development of a low-temperature processed electron-transporting layers (ETL) is highly desirable for high-performance planar perovskite solar cells (PSCs) toward large-scale and flexible devices, yet remains a great challenge. Herein, a low-temperature route was applied to synthesize FeOOH quantum dots (QDs) as promsing ETL for PSCs. A systematic survey of the structure, morphology and band structure was carried out, and the device performance further illustrates that the device based on FeOOH QDs ETL achieves a high efficiency of 17.3% with negligible hysteresis. Moreover, a stable current output at 0.8 V in 400 s was observed in the champion device. As a result, the low-temperature preparation of FeOOH QDs ETL and the corresponding excellent performance of PSCs present great commercial potential for future applications.