Donor-Interacting Arylated Carbazole Self-Assembled Monolayer Enables Highly Efficient and Stable Organic Photovoltaics

Yiwen Wang; Wenlin Jiang; Le Mei; Xiankai Chen; Min Sun; Chieh-Ting Lin; Rui Zhang; Gengxin Du; Weiming Qiu; Xi Yang; Qunping Fan; Hin-Lap Yip; Francis R Lin; Alex K-Y Jen

doi:10.1002/smll.202403233

Donor-Interacting Arylated Carbazole Self-Assembled Monolayer Enables Highly Efficient and Stable Organic Photovoltaics

Small. 2025 Jan 15:e2403233. doi: 10.1002/smll.202403233. Online ahead of print.

Authors

Yiwen Wang^{1

2

3}, Wenlin Jiang^{2

3}, Le Mei⁴, Xiankai Chen^{5

6}, Min Sun⁷, Chieh-Ting Lin⁷, Rui Zhang⁸, Gengxin Du^{2

3}, Weiming Qiu⁹, Xi Yang⁹, Qunping Fan¹⁰, Hin-Lap Yip^{2

3

11

12}, Francis R Lin^{2

3

4}, Alex K-Y Jen^{2

3

4

12}

Affiliations

¹ Institute of New Energy Technology, College of Physics and Optoelectronic Engineering, Jinan University, Guangzhou, 510632, China.
² Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong, 999077, China.
³ Hong Kong Institute for Clean Energy (HKICE), City University of Hong Kong, Kowloon, Hong Kong, 999077, China.
⁴ Department of Chemistry, City University of Hong Kong, Kowloon, Hong Kong, 999077, China.
⁵ Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, 215123, China.
⁶ Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, 215123, China.
⁷ Department of Chemical Engineering, National Chung Hsing University, Taichung, 40227, Taiwan.
⁸ Department of Physics, Chemistry and Biology, Linköping University, Linköping, SE-581 83, Sweden.
⁹ Guangzhou Chasinglight Technology Co. Ltd, Guangzhou, 510535, China.
¹⁰ State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, China.
¹¹ School of Energy and Environment, City University of Hong Kong, Kowloon, Hong Kong, 999077, China.
¹² State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong, 999077, China.

PMID: 39811959
DOI: 10.1002/smll.202403233

Abstract

Carbazole-derived self-assembled monolayers (SAMs) are promising materials for hole-extraction layer (HEL) in conventional organic photovoltaics (OPVs). Here, a SAM Cbz-2Ph derived from 3,6-diphenylcarbazole is demonstrated. The large molecular dipole moment of Cbz-2Ph allows the modulation of electrode work function to facilitate hole extraction and maximize photovoltage, thus improving the OPV performance. Additionally, the flanking aryls of Cbz-2Ph help establish CH-π interactions for forming a dense and well-organized SAM HEL and exhibit stronger van der Waals interactions with the donor PM6 than acceptor BTP-eC9. The stronger SAM-donor interactions modulate the PM6 distribution in PM6:BTP-eC9 bulk-heterojunction film, leading to PM6 enrichment near HEL to facilitate efficient hole extraction to the ITO anode in conventional p-i-n OPVs. Consequently, binary PM6:BTP-eC9-based devices incorporating the Cbz-2Ph HEL demonstrate an impressive efficiency of 19.18%. These cells also showcase excellent operational stability, with a T₈₀ lifetime of ≈1260 h at the maximum power point, over 10 times longer than those using the traditional PEDOT:PSS HEL (T₈₀ ≈96 h). Furthermore, the universal applicability of Cbz-2Ph as a HEL is evident through its successful implementation in PM6:BTP-eC9:L8-BO-F-based ternary devices and PM6:BTP-eC9-based printed OPV devices, achieving a PCE of 19.30% and 16.96%, respectively.

Keywords: charge extraction layer; molecular interaction; organic photovoltaics; photostability; self‐assembled monolayer.

Abstract

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