Issue 43, 2020

Design of narrow bandgap non-fullerene acceptors for photovoltaic applications and investigation of non-geminate recombination dynamics

Abstract

A new narrow bandgap non-fullerene electron acceptor was designed, synthesized, and characterized for near-infrared organic photovoltaics. This acceptor was compared to a structurally similar compound with systematically modified side chains, and a series of solar cells were fabricated, employing the common donor polymers PTB7-Th and PBDBT. The devices exhibited charge generation over a wide spectral range and power conversion efficiencies up to 8.1%. The non-geminate recombination dynamics were investigated and quantified via a combination of capacitance spectroscopy and transient open-circuit voltage decay measurements. The reduction of the bandgap results in increased bimolecular recombination losses, while solar cells composed of PBDBT were afflicted by stronger monomolecular, i.e. trap-assisted, recombination losses that ultimately caused the lower power conversion efficiencies of the respective devices. The latter observation could be correlated to less ordered blend film morphology.

Graphical abstract: Design of narrow bandgap non-fullerene acceptors for photovoltaic applications and investigation of non-geminate recombination dynamics

Supplementary files

Article information

Article type
Paper
Submitted
01 5 2020
Accepted
01 7 2020
First published
01 7 2020

J. Mater. Chem. C, 2020,8, 15175-15182

Author version available

Design of narrow bandgap non-fullerene acceptors for photovoltaic applications and investigation of non-geminate recombination dynamics

J. Vollbrecht, J. Lee, S. Ko, V. V. Brus, A. Karki, W. Le, M. Seifrid, M. J. Ford, K. Cho, G. C. Bazan and T. Nguyen, J. Mater. Chem. C, 2020, 8, 15175 DOI: 10.1039/D0TC02136A

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