Solution-Processable ZnO/Carbon Quantum Dots Electron Extraction Layer for Highly Efficient Polymer Solar Cells.

Research paper by Ruqin R Zhang, Min M Zhao, Zhongqiang Z Wang, Zongtao Z Wang, Bo B Zhao, Yanqin Y Miao, Yingjuan Y Zhou, Hua H Wang, Yuying Y Hao, Guo G Chen, Furong F Zhu

Indexed on: 18 Jan '18Published on: 18 Jan '18Published in: ACS Applied Materials & Interfaces


In this work, we report the effort to develop high efficiency inverted polymer solar cells (PSCs) by applying a solution processable bilayer ZnO/carbon quantum dots (C-QDs) electron extraction layer (EEL). It is shownthat the use of the bilayerEEL helps to suppress the exciton quenching by passivating the ZnO surface defects in the EEL, leading to an enhanced exciton dissociation, reduced charge recombinationand more efficient charge extraction probability, and thereby achieving high power conversion efficiency (PCE). The inverted PSCs, based on the blend of poly{4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl-alt-3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophene-4,6-diyl} and [6,6]-phenyl C71-butyric acid methyl ester, possess a significant improvement in PCE of ~9.64%, which is >27% higher than that of a control cell (~7.59%). The use of a bilayer ZnO/C-QDs EEL offers a promising approach for attaining high efficiency inverted PSCs.