title: Enhanced performance of polymer solar cells by employing a ternary cascade energy structure.
abstract: We present a route to successfully tackle the two main limitations, low open circuit voltage (Voc) and limited short circuit-density (Jsc), of polymer solar cells (PSCs) based on poly(3-hexylthiophene) (P3HT) as an electron-donor. The indene-C60 bisadduct (ICBA) was selected as an electron acceptor to improve the open circuit voltage (Voc). The narrow band gap polymer poly[(4,8-bis-(2-ethylhexyloxy)-benzo[1,2-b:4,5-b']dithiophene)-2,6-diyl-alt-(4-(2-ethylhexanoyl)-thieno[3,4-b]thiophene)-2,6-diyl] (PBDTTT-C), as a complementary electron-donor material, was doped into the host system of P3HT:ICBA to form ternary cascade energy structured PSCs with increased Jsc. The power conversion efficiency (PCE) of P3HT:ICBA-based cells was improved from 3.32% to 4.38% by doping with 3 wt% PBDTTT-C with 1 min 150 °C annealing treatment. The 4.38% PCE of ternary PSCs is still larger than the 3.79% PCE of PSCs based on P3HT:ICBA with 10 minutes 150 °C annealing treatment.
authors: Key Laboratory of Luminescence and Optical Information, Ministry of Education, Beijing Jiaotong University, 100044, China. fjzhang@bjtu.edu.cn fteng@bjtu.edu.cn.
authors: Qiaoshi
authors: Q
authors: An
authors: Fujun
authors: F
authors: Zhang
authors: Lingliang
authors: L
authors: Li
authors: Zuliang
authors: Z
authors: Zhuo
authors: Jian
authors: J
authors: Zhang
authors: Weihua
authors: W
authors: Tang
authors: Feng
authors: F
authors: Teng