Interface passivation and electron transport improvement via employing calcium fluoride for polymer solar cells

JOURNAL OF COLLOID AND INTERFACE SCIENCE

卷:562

Article

Tang, Yuting¹  Pang, Yu¹  Li, Xu¹  Zong, Beibei¹  Kang, Bonan¹  Silva, S. Ravi P.²  Lu, Geyu¹ 

[1] Jilin Univ, Coll Elect Sci & Engn, State Key Lab Integrated Optoelect, 2699 Qianjin St, Changchun 130012, Peoples R China

[2] Univ Surrey, Nanoelect Ctr, Adv Technol Inst, Guildford GU2 7XH, Surrey, England

关键词: Interface passivation;    Polymer solar cells;    CaF2 layer;    Surface traps;    Interfacial barrier;   

DOI  :  10.1016/j.jcis.2019.12.025

来源: Elsevier

【 摘 要 】

To enhance the performance of inverted structure polymer solar cells (PSCs), interfacial engineering considered as an effective and straightforward method was employed. In this study, to overcome the surface traps and energy level mismatches of the electron transport layer, a means of interface passivation by evaporating an ultrathin CaF2 layer above ZnO thin film as the electron transport layer was successfully adopted. We display that CaF2 layer could passivate the surface traps of ZnO thin film and decrease the interfacial barrier between PC61BM and ZnO, so that electron transfer efficiency is facilitated, the recombination of electrons and holes is inhibited at the contact interface, and the series resistance is reduced. After the introduction of the CaF2 layer, the short-circuit current and the fill factor was greatly improved, also the power conversion efficiency (PCE) was increased from 3.21% of the reference device without the CaF2 layer to 4.22% in the inverted PSCs based on P3HT:PC61BM bulk heterojunction photoactive layer. These results could have special guiding significance for high-efficiency PSCs and also great potential for applications of photovoltaic devices in the future. (C) 2019 Published by Elsevier Inc.

【 授权许可】

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