In this work, a series of polymer bulk-heterojunctions is fabricated based on the combinations of different donors （Ds） （P3HT and PCPDTBT） and acceptors （As） （PCBM, ICBA, and F8BT）. Exciton quenching efficienc...In this work, a series of polymer bulk-heterojunctions is fabricated based on the combinations of different donors （Ds） （P3HT and PCPDTBT） and acceptors （As） （PCBM, ICBA, and F8BT）. Exciton quenching efficiencies of the D-A pairs are obtained in order to quantify charge-transfer between the donor and the acceptor via a modified approach developed in conjunction with experimental results of optical absorption and photoluminescence spectra. It is discovered that the exciton quenching efficiency in the combination of PCPDTBT：PCBM and P3HT：PCBM reaches 70% and over, but in PCPDTBT：ICBA it is about 12%. A relatively high ALUMOdonor_acceptor results in a relatively high exciton quenching efficiency, which is responsible for better charge separation. The results agreed well with the photocurrent effect of the heterojunction layers. The work offers a convenient way to predict a potentially promising photovoltaic material with a selected D-A pair.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.21174016 and 11474017)the Fundamental Research Funds for the Central Universities(Grant No.2013JBZ004)the Research Fund for the Doctoral Program of Higher Education of China(Grant No.20120009110031)
文摘In this work, a series of polymer bulk-heterojunctions is fabricated based on the combinations of different donors （Ds） （P3HT and PCPDTBT） and acceptors （As） （PCBM, ICBA, and F8BT）. Exciton quenching efficiencies of the D-A pairs are obtained in order to quantify charge-transfer between the donor and the acceptor via a modified approach developed in conjunction with experimental results of optical absorption and photoluminescence spectra. It is discovered that the exciton quenching efficiency in the combination of PCPDTBT：PCBM and P3HT：PCBM reaches 70% and over, but in PCPDTBT：ICBA it is about 12%. A relatively high ALUMOdonor_acceptor results in a relatively high exciton quenching efficiency, which is responsible for better charge separation. The results agreed well with the photocurrent effect of the heterojunction layers. The work offers a convenient way to predict a potentially promising photovoltaic material with a selected D-A pair.
