Efficient all-small-molecule organic solar cells processed with non-halogen solvent

Wei Gao; Ruijie Ma; Top Archie Dela Peña; Cenqi Yan; Hongxiang Li; Mingjie Li; Jiaying Wu; Pei Cheng; Cheng Zhong; Zhanhua Wei; Alex K-Y Jen; Gang Li

doi:10.1038/s41467-024-46144-8

Efficient all-small-molecule organic solar cells processed with non-halogen solvent

Nat Commun. 2024 Mar 2;15(1):1946. doi: 10.1038/s41467-024-46144-8.

Authors

Wei Gao^#¹, Ruijie Ma^#², Top Archie Dela Peña^#^{3

4}, Cenqi Yan⁵, Hongxiang Li⁶, Mingjie Li³, Jiaying Wu⁴, Pei Cheng⁵, Cheng Zhong⁷, Zhanhua Wei¹, Alex K-Y Jen^{8

9}, Gang Li¹⁰

Affiliations

¹ Xiamen Key Laboratory of Optoelectronic Materials and Advanced Manufacturing, Institute of Luminescent Materials and Information Displays, College of Materials Science and Engineering, Huaqiao University, Xiamen, 361021, China.
² Department of Electrical and Electronic Engineering, Research Institute for Smart Energy (RISE), The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, 999077, China. [email protected].
³ Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, 999077, China.
⁴ Advanced Materials Thrust, Function Hub, The Hong Kong University of Science and Technology, Nansha, Guangzhou, 511442, China.
⁵ College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu, 610064, China.
⁶ College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu, 610064, China. [email protected].
⁷ Department of Chemistry, Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, Wuhan University, Wuhan, 430072, China.
⁸ Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, 999077, Hong Kong, China. [email protected].
⁹ Hong Kong Institute for Clean Energy, City University of Hong Kong, Kowloon, 999077, Hong Kong, China. [email protected].
¹⁰ Department of Electrical and Electronic Engineering, Research Institute for Smart Energy (RISE), The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, 999077, China. [email protected].

^# Contributed equally.

Abstract

All-small-molecule organic solar cells with good batch-to-batch reproducibility combined with non-halogen solvent processing show great potential for commercialization. However, non-halogen solvent processing of all-small-molecule organic solar cells are rarely reported and its power conversion efficiencies are very difficult to improve. Herein, we designed and synthesized a small molecule donor BM-ClEH that can take advantage of strong aggregation property induced by intramolecular chlorine-sulfur non-covalent interaction to improve molecular pre-aggregation in tetrahydrofuran and corresponding micromorphology after film formation. Tetrahydrofuran-fabricated all-small-molecule organic solar cells based on BM-ClEH:BO-4Cl achieved high power conversion efficiencies of 15.0% in binary device and 16.1% in ternary device under thermal annealing treatment. In contrast, weakly aggregated BM-HEH without chlorine-sulfur non-covalent bond is almost inefficient under same processing conditions due to poor pre-aggregation induced disordered π-π stacking, indistinct phase separation and exciton dissociation. This work promotes the development of non-halogen solvent processing of all-small-molecule organic solar cells and provides further guidance.

Abstract

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