Simple-Structured NIR-Absorbing Small-Molecule Acceptors with a Thiazolothiazole Core: Multiple Noncovalent Conformational Locks and D-A Effect for Efficient OSCs

Wenhong Peng; Guangjun Zhang; Mengbing Zhu; Hao Xia; Yingshuang Zhang; Hua Tan; Yu Liu; Weijie Chi; Qiang Peng; Weiguo Zhu

doi:10.1021/acsami.9b16686

Simple-Structured NIR-Absorbing Small-Molecule Acceptors with a Thiazolothiazole Core: Multiple Noncovalent Conformational Locks and D-A Effect for Efficient OSCs

ACS Appl Mater Interfaces. 2019 Dec 26;11(51):48128-48133. doi: 10.1021/acsami.9b16686. Epub 2019 Dec 11.

Authors

Affiliations

¹ School of Materials Science and Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications, Jiangsu Key Laboratories of Environment-Friendly Polymers, National Experimental Demonstration Center for Materials Science and Engineering , Changzhou University , Changzhou 213164 , China.
² Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, and State Key Laboratory of Polymer Materials Engineering , Sichuan University , Chengdu 610064 , China.
³ Fluorescence Research Group , Singapore University of Technology and Design , 8 Somapah Road , Singapore 487372 , Singapore.

PMID: 31774648
DOI: 10.1021/acsami.9b16686

Abstract

Developing simple-structured and efficient near-infrared (NIR) absorbing small-molecule acceptors (SMAs) remains of great importance for commercial applications in organic solar cells (OSCs). Herein, we construct two novel thiazolothiazole-centered NIR-absorbing SMAs by alkoxy/alkylthio side chains (TTz3/TTz4) and multiple noncovalent conformational locks of S···N, S···O, and S···S. These conformational locks make both simple-structured SMAs exhibit an extended planar configuration and a red-shifted NIR absorption in comparison with the SMA with an alkyl side chain (TTz1). As expected, both SMAs show high-efficiency photovoltaic performance in the solution-processing OSCs using J71 as a donor. A higher power conversion efficiency of 8.76% with a low energy loss (0.57 eV) is obtained in the TTz3-based OSCs. It is the first report on the simple-structured and efficient NIR-absorbing SMAs, which have great potential applied in the semitransparent OSCs.

Keywords: NIR-absorbing; organic solar cells; side chains; small molecule acceptors; thiazolothiazole.