Surface-deprotonated ultra-small SnO2 quantum dots for high-performance perovskite solar cells

Abstract

SnO₂ electron transport layers (ETLs) have improved perovskite solar cell (PSC) efficiencies but face issues with surface protonation, leading to energy loss and instability. We developed ultra-small (2.5 nm) SnO₂ quantum dots (QDs) ETLs that are surface-deprotonated. These ETLs reduce interface barriers and enhance electron transfer efficiency. PSCs using these SnO₂ QDs achieved a champion efficiency of 25.55% and improved stability, outperforming protonated SnO₂ QDs. Additionally, these ETLs showed superior performance in X-ray detectors.