Molecular Doping Inhibits Charge Trapping in Low-Temperature-Processed ZnO toward Flexible Organic Solar Cells

• DOI: 10.1021/acsami.0c23087
• Publication Date: 2021-03-18T15:59:25Z
• Authors: Yiqiu Xia; Chen Wang; Biao Dong; Ge Wang; Yi Chen; Roderick C. I. Ma...; Wei Dong; Shengping Ruan; Yizhan Liu; Shanpeng Wen
• Keywords: Organic Electronics; HOMO/LUMO

There has been a growing interest in the development of efficient flexible organic solar cells (OSCs) due to their unique capacity provide energy sources for electronics. To this end, it is required design compatible interlayer with low processing temperature and high electronic quality. In work, we present that quality ZnO fabricated from low-temperature (130 °C) sol–gel method can be significantly improved by doping an small molecule, TPT-S. The doped TPT-S, on one hand, passivates uncoordinated Zn-related defects forming N–Zn bonds. On other photoinduced charge transfer TPT-S confirmed, which further fills up electron-deficient trap states. This renders electron transport capability reduced recombination. By illuminating devices square light pulses varying intensities, also reveal unfavorable trapping/detrapping process observed low-temperature-processed inhibited after doping. OSCs based PBDB-T-2F:IT-4F ZnO:TPT-S being cathode yield efficiencies 12.62 11.33% rigid substrates, respectively. These observations convey practicality such hybrid high-performance devices.