Organic–inorganic hybrid perovskite solar cells have become one of the highly promising candidates for photovoltaic technologies because of their low processing cost, rapid-growing power conversion efficiency and easy preparation process. Electron transfer layer (ETL) plays an important role in exciton separation and charge transport for perovskite devices. A TiO2–ZnO binary mixed nanoparticle (NP) ETL, which can be prepared in low-temperature hydrothermal method, was proposed. By analyzing the XRD and SEM, the incorporation of mixed NPs thin film improved the interfacial stability of ZnO/perovskite and prevented the perovskite layer from being decomposed as compared to the pure ZnO NPs thin film. Furthermore, UV spectrum and EIS results show that TiO2–ZnO mixed NP ETL has high transmittance and maintains good electrical properties of pure ZnO NPs basically. Finally, the efficiency of perovskite device based on TiO2–ZnO mixed NP ETL was improved to 15%. Our research provides a simple way for the application of ZnO in PCSs.
All-Nanoparticle SnO2/TiO2 Electron-Transporting Layers Processed at Low Temperature for Efficient Thin-Film Perovskite Solar Cells