Fabrication of UV-Stable Perovskite Solar Cells with Compact Fe(2)O(3) Electron Transport Layer by FeCl(3) Solution and Fe(3)O(4) Nanoparticles

Even though Fe(2)O(3) is reported as the electron-transporting layer (ETL) in perovskite solar cells (PSCs), its fabrication and defects limit its performance. Herein, we report a Fe(2)O(3) ETL prepared from FeCl(3) solution with a dopant Fe(3)O(4) nanoparticle modification. It is found that the mixed solution can reduce the defects and enhance the performance of Fe(2)O(3) ETL, contributing to improved electron transfer and suppressed charge recombination. Consequently, the best efficiency is improved by more than 118% for the optimized device. The stability efficiency of the Fe(2)O(3)-ETL-based device is nearly 200% higher than that of the TiO(2)-ETL-based device after 7 days measurement under a 300 W Xe lamp. This work provides a facile method to fabricate environmentally friendly, high-quality Fe(2)O(3) ETL for perovskite photovoltaic devices and provides a guide for defect passivation research.