Issue 7, 2018

Understanding the influence of carboxylate substitution on the property of high-performance donor polymers in non-fullerene organic solar cells

Abstract

Carboxylate substitution is a common approach to tune the energy level of donor polymers for organic solar cells. However, the influence of carboxylate substitution on the morphological and electronic properties of donor polymers is not well understood. In this paper, we study two pairs of structurally similar terthiophene or quarterthiophene donor polymers with partial or complete carboxylate substitution on the alkyl side chains. It is found that the carboxylate substitution can enhance the crystallinity of the donor polymers and introduce larger and purer domains. Moreover, the polymers with the carboxylate substitution exhibit reduced bimolecular recombination due to the improved morphology. For device efficiencies, the terthiophene-based polymer, P3TEA (with 50% carboxylate substitution), exhibits the best performance. The alkyl side chains on P3TEA provide a typical temperature-dependent aggregation property, allowing for effective morphology control, while the carboxylate substitution deepens the HOMO level and enhances the crystallinity of the polymer. These benefits yield a near optimal morphology and high Voc value, and thus the best device efficiency among the polymers studied.

Graphical abstract: Understanding the influence of carboxylate substitution on the property of high-performance donor polymers in non-fullerene organic solar cells

Supplementary files

Article information

Article type
Research Article
Submitted
12 Mär 2018
Accepted
23 Apr 2018
First published
11 Mai 2018

Mater. Chem. Front., 2018,2, 1360-1365

Understanding the influence of carboxylate substitution on the property of high-performance donor polymers in non-fullerene organic solar cells

G. Yang, J. Liu, L. Ma, S. Chen, J. Y. L. Lai, W. Ma and H. Yan, Mater. Chem. Front., 2018, 2, 1360 DOI: 10.1039/C8QM00101D

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