Improving the Performance of a Perovskite Solar Cell by Adjusting the Dispersant for Titanium Dioxide

Abstract The electron‐transport layer (ETL) plays an important role in the photovoltaic performance of perovskite solar cells (PSCs). In this work, titanium dioxide (TiO 2 ) nanoparticles are synthetized by a hydrothermal method. The as‐synthesized TiO 2 is dispersed into different alcoholic solvents with different lengths of the carbon chain. The TiO 2 ETL is fabricated by spin‐coating TiO 2 paste onto a TiO 2 blocking layer/FTO. Scanning electron microscopy, atomic force microscopy, steady‐state photoluminescence, time‐resolved photoluminescence, and the photovoltaic performance of the samples and devices are investigated. The results show that the n ‐pentanol dispersant can effectively reduce the pinholes and trap states of the TiO 2 ETL layer, which enhances the charge carrier transport efficiency and reduces charge recombination. The device achieves an optimal power conversion efficiency of 18.16 %, which is an increase by 23.28 % compared to the common method of using ethanol as the dispersant.