Inverted polymer solar cells using CdS fabricated by thermal decomposition of cadmium xanthate precursor as electron transporting layer

In this manuscript, CdS thin films fabricated by thermal decomposition of the solution processable cadmium xanthate precursor were used as electron transporting layer (ETL) in inverted polymer solar cells (IPSCs) with device structure ITO/CdS/poly(3-hexylthiophene-2,5-diyl) (P3HT):[6,6]-phenyl C-61 butyric acid methyl ester (PC61BM)/MoO3/Ag. The effects of CdS thickness and the annealing temperature of cadmium xanthate precursor on the photovoltaic performance of IPSCs were investigated. The highest power conversion efficiency (PCE) value of 3.22% was obtained when CdS thin film thickness was 10 nm and the annealing temperature of cadmium xanthate precursor was 160 degrees C. This value is slightly higher than that of the IPSC with device structure ITO/ZnO/P3HT:PC61BM/MoO3/Ag using sol-gel derived ZnO thin films as ETL. The results indicate that CdS films deposited by thermal decomposition of metal xanthate precursor are excellent ETL for IPSCs. (C) 2016 Elsevier Ltd. All rights reserved.