Compact TiO2/Anatase TiO2 Single-Crystalline Nanoparticle Electron-Transport Bilayer for Efficient Planar Perovskite Solar Cells

Abstract

Electron-transport layer (ETL)/perovskite interface modification plays a key task for producing efficient planar perovskite solar cells (PSCs). In this study, interfacial modification of compact TiO2 using novel, one-step hydrothermally synthesized single-crystalline anatase (AT) titania nanoparticles (TiO2 NPs) (average diameter = 6–10 nm) was applied as an ETL bilayer to enhance the efficient charge generation and extraction and eliminate the electron–hole recombination ratio. We report here an easy approach for enhancing the performance of planar PSCs by introducing a compact TiO2/AT TiO2 NPs bilayer through spray pyrolysis (SP) deposition and spin-coating (SC) techniques, respectively. The enhanced performance of the devices with an SP-TiO2/SC-AT TiO2 NPs bilayer facilitated more efficient electron transport, charge extraction, and low interfacial recombination. Ultimately, the best device had a 17.05% power conversion efficiency resulting from the significant decrease in J–V hysteresis, presenting al...