Issue 47, 2018

Simple-structured small molecule acceptors constructed by a weakly electron-deficient thiazolothiazole core for high-efficiency non-fullerene organic solar cells

Abstract

Non-fullerene organic solar cells (OSCs) have attracted significant attention recently due to their tremendous advances in power conversion efficiency (PCE). It has been found that most non-fullerenes are small molecule acceptors (SMAs) bearing electron-rich cores of polycyclic arenes. However, these polycyclic arenes have a high synthetic cost. Here, a novel strategy is proposed to construct SMAs using simple and weakly electron-deficient thiazolothiazole (TTz) as the core. Two simple-structured SMAs of TTz1 and TTz2 with an A(π–A′–A′′)2 framework are designed and synthesized for potential applications in OSCs, in which benzothiadiazole and malononitrile derivatives are employed as a dual electron-accepting (A′–A′′) arm. Their optical, electrochemical and photovoltaic performances are systematically investigated. We find that both TTz1 and TTz2 exhibit decreased LUMO and increased HOMO energy levels in comparison to the prototypical small molecules TT0 and TTz0 bearing a single electron-accepting (A′′) terminal end. Medium optical bandgap of about 1.60 eV and satisfactory energy levels are obtained for both molecules TTz1 and TTz2 with more balanced carrier mobility by introducing a novel TTz core and tuning the A′–A′′ arm. The highest PCE value of 8.77% is recorded in TTz1-based OSCs blended with the common electron-donating material J71, which is the highest efficiency among OSCs using simple-structured SMAs as non-fullerenes to date. This study reveals great potential to construct high-efficiency and simple-structured SMAs using a weakly electron-deficient TTz core instead of an electron-donating polycyclic arene core.

Graphical abstract: Simple-structured small molecule acceptors constructed by a weakly electron-deficient thiazolothiazole core for high-efficiency non-fullerene organic solar cells

Supplementary files

Article information

Article type
Paper
Submitted
27 Sept. 2018
Accepted
02 Nov. 2018
First published
05 Nov. 2018

J. Mater. Chem. A, 2018,6, 24267-24276

Simple-structured small molecule acceptors constructed by a weakly electron-deficient thiazolothiazole core for high-efficiency non-fullerene organic solar cells

W. Peng, G. Zhang, L. Shao, C. Ma, B. Zhang, W. Chi, Q. Peng and W. Zhu, J. Mater. Chem. A, 2018, 6, 24267 DOI: 10.1039/C8TA09370A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements