title: Photomultiplication photodetectors with P3HT:fullerene-free material as the active layers exhibiting a broad response.
abstract: A series of polymer photodetectors (PPDs) are fabricated based on P3HT as an electron donor and fullerene-free material DC-IDT2T as an electron acceptor. The only difference among these PPDs is the P3HT:DC-IDT2T doping weight ratios from 2 : 1 to 150 : 1. The PPDs with P3HT:DC-IDT2T (100 : 1, w/w) as the active layers exhibit champion external quantum efficiency (EQE) of 28 000% and 4000% corresponding to 390 nm and 750 nm light illumination at -20 V bias, respectively. The photomultiplication (PM) phenomenon should be attributed to the enhanced hole tunneling injection due to the interfacial band bending, which is induced by the trapped electrons in DC-IDT2T near the Al cathode. The high EQE value in the long wavelength range is due to the effect of DC-IDT2T photon harvesting and exciton dissociation on the interfacial trap-assisted hole tunneling injection. Meanwhile, the PPDs with DC-IDT2T as the electron acceptor exhibit superior stability compared with the PPDs with PC71BM as the electron acceptor.
authors.affiliation: Key Laboratory of Luminescence and Optical Information, Ministry of Education, Beijing Jiaotong University, Beijing 100044, People's Republic of China. fjzhang@bjtu.edu.cn.
authors.forename: Wenbin
authors.initials: W
authors.lastname: Wang
authors.affiliation: Key Laboratory of Luminescence and Optical Information, Ministry of Education, Beijing Jiaotong University, Beijing 100044, People's Republic of China. fjzhang@bjtu.edu.cn.
authors.forename: Fujun
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Department of Materials Science and Engineering, College of Engineering, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, Peking University, Beijing 100871, People's Republic of China. xwzhan@pku.edu.cn.
authors.forename: Huitao
authors.initials: H
authors.lastname: Bai
authors.affiliation: Key Laboratory of Luminescence and Optical Information, Ministry of Education, Beijing Jiaotong University, Beijing 100044, People's Republic of China. fjzhang@bjtu.edu.cn.
authors.forename: Lingliang
authors.initials: L
authors.lastname: Li
authors.affiliation: Key Laboratory of Luminescence and Optical Information, Ministry of Education, Beijing Jiaotong University, Beijing 100044, People's Republic of China. fjzhang@bjtu.edu.cn.
authors.forename: Mile
authors.initials: M
authors.lastname: Gao
authors.affiliation: Key Laboratory of Luminescence and Optical Information, Ministry of Education, Beijing Jiaotong University, Beijing 100044, People's Republic of China. fjzhang@bjtu.edu.cn.
authors.forename: Miao
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Department of Materials Science and Engineering, College of Engineering, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, Peking University, Beijing 100871, People's Republic of China. xwzhan@pku.edu.cn.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Zhan