Time-resolved photocurrent of an organic-inorganic hybrid solar cell based on Sb2S3

Abstract

In this study, the optical and the electrical properties of a hybrid solar cell (SC) based on a zinc oxide (ZnO)/antimony trisulfide (Sb2S3)/poly(3-hexylthiophene) (P3HT) heterojunction were investigated. ZnO and Sb2S3 films were grown using atomic layer deposition (ALD). Photoluminescence (PL) spectra show band-to-band emission of the Sb2S3 layer at around 724 nm at room temperature. The room-temperature current decay behaviors were investigated based on the time-resolved photocurrent (TRPC). With increasing intensity (P) of the excitation pulse laser, the current decay time gradually decreased due to an enhancement of the carrier recombination. Optically biased TRPC was demonstrated with energies above and below the band gap of Sb2S3 to investigate the effect of the background carrier concentration during carrier transport. We found three carrier exhaustion processes during carrier transport due to the recombination behaviors at given carrier injection levels. At high injection level, the current decay times were also affected by the hole diffusion rate in the P3HT h-conducting layer. © 2016, The Korean Physical Society.