All-porphyrin organic solar cells

作者:Pan, Xiaojie; Huang, Siyu; Zhu, Bei; Xia, Ruidong; Peng, Xiaobin*
来源:Dyes and Pigments, 2020, 180: 108503.
DOI:10.1016/j.dyepig.2020.108503

摘要

Four small molecule electron acceptors TEH-PDI, TEH-DPDI, TPDI and TDPDI based on a porphyrin core and perylene bisimides (PDI) units were designed and synthesized. The energy levels and aggregation properties of the four acceptors were tuned to match those of a porphyrin electron donor C19OD-DPP based on a porphyrin core and 1,4-diketopyrrolo[3,4-c]pyrroles (DPP) end groups by adjusting the number of PDI units and the connection manners to a porphyrin core synergistically. The all-porphyrin bulk heterojunction (BHJ) solar cells exhibit panchromatic photon-to-current conversion from 300 to 900 nm with a small valley around 650 nm and provide power conversion efficiencies (PCEs) of 0.11%-2.57% when the active layers were prepared in the presence of octane-1,8-dithiol (ODT) additive. Further investigations show that more balanced hole/electron mobility, less trap-assisted monomolecular recombination and bimolecular recombination are beneficial for achieving higher J(SC) and PCE for C19OD-DPP/TPDI devices.