Chemical bath deposited SnO2 for high-efficiency perovskite solar cells on Ti substrates

Abstract

Perovskite solar cells fabricated on metal substrates, such as Ti, can effectively reduce manufacturing costs. However, the SnO2 electron transport layers (ETL) deposited using most methods is not suitable for Ti substrates, resulting in low-efficiency devices. This study improved the chemical bath technology to facilitate the easy deposition of SnO2 layers with a low oxygen defect concentration and high conductivity on Ti substrates by adjusting the reaction time. The devices fabricated on Ti substrate using optimized SnO2 showed a much higher short-circuit current density (Jsc) and fill factor (FF) compared to control devices. The champion device demonstrated a Jsc of 20.1 mA/cm2 and a power conversion efficiency (PCE) of 15.21%. Additionally, we proposed solutions to fabricate a large perovskite solar cell module with a 12.96 cm2 aperture area and 95.8% geometric filling factor (GFF). This metal substrate–based approach was developed by taking the preparation technology of C–Si solar cells as a reference.