Influence of insulating oxide coatings on the performance of perovskite solar cells and the interface charge recombination dynamics

Abstract

Insulating oxides of SiO2, ZrO2, and Al2O3 were coated using a dipping method on the surface of mesoporous TiO2nanoparticles for perovskite solar cells. The effects of the insulating oxide coatings on the performance of the perovskite solar cells and the interface charge recombination dynamics were investigated in detail. The efficiency of devices after SiO2 coating improved by 13.7% due to their FF (fill factor) increasing from 67.6% to 72.3%. However, the devices with ZrO2and Al2O3 coatings exhibited an increase in Voc of up to 50 mV and a decrease in Jsc and FF. Transient absorption spectroscopy on a timescale from nanoseconds to milliseconds was performed to study the interface recombination lifetime between electrons and holes and the changes of the device performances are discussed.