The optical and electrical properties regulation of TiO2 mesoporous thin film in perovskite solar cells

In this work, we investigate how TiO 2 nanotube and nanosheet composite mesoporous TiO 2 layers can improve the power conversion efficiency (PCE) of perovskite solar cells (PSCs) with respect to pure mesoporous TiO 2 . Pure and nanotube/nanosheet composite TiO 2 , nanostructure of three different concentrations (0.5, 1, and 3 mol%) were synthesized by a simple, hydrothermal method and characterized by XRD, SEM, transmission electron microscopy (TEM), and UV–Vis diffuse reflection spectroscopy. TiO 2 nanotubes and TiO 2 nanosheets were incorporated into the TiO 2 porous layer of perovskite solar cell, which outperform cells using pure TiO 2 in several ways: higher open-circuit voltage ( V oc ) (1.06 V), power conversion efficiency (PCE) (15.58%), short-circuit current ( J sc ), and fill factor (FF). These properties improvements are attributed to the better properties of modulated TiO 2 as compared to TiO 2 such as better optical transmission properties, faster electron transfer rate and higher electron lifetime. This work provides a simple and effective strategy to improve TiO 2 porous layer, which is significant for the study of the cell porous layer in perovskite solar.