Thermally activated, light-induced electron-spin-resonance spin density reflected by photocurrents in a perovskite solar cell

Abstract

Light-induced electron-spin-resonance (LESR) spin density in a perovskite solar cell (PSC) is ascribed to photo-induced charges accumulated at the interface of the perovskite and the hole transport layer (HTL). The LESR spin density was observed to he decreased as the temperature was lowered from room temperature to 170 K in a PSC; below similar to 170 K, no LESR was found. Meanwhile, the photocurrent showed only an similar to 25% decrease between room temperature and 170 K. The comparison of LESR in temperature-dependence with transient or steady photocurrents suggested that the decrease in photocurrent at the low temperatures stems mainly from trapping of delocalized holes at the interface of perovskite and HTL. Published. under license by AIP Publishing.