Suppression of geminate charge recombination in organic photovoltaic devices with a cascaded energy heterojunction

Groves, C.

Abstract

The effect of cascaded energy heterojunctions on geminate charge recombination in organic photovoltaic devices is examined using a kinetic Monte Carlo model. The structure of the cascaded heterojunction, which encourages spatial separation of the geminate charge pair, is varied to recreate that found in ternary blends and tri-layers, as well as that formed by self-organization in binary blends in which one component crystallizes. It is shown that substantial reductions in charge recombination can indeed be achieved with parameters similar that reported for P3HT:PCBM solar cells. However, the efficacy of cascaded energy heterojunctions is shown to be limited for thick cascade layers (>10 nm). This provides guidance as how to design ternary organic photovoltaics, whilst also offering a possible explanation of low recombination efficiency in some semi-crystalline OPVs.

Citation

Groves, C. (2013). Suppression of geminate charge recombination in organic photovoltaic devices with a cascaded energy heterojunction. Energy & Environmental Science, 6(5), 1546-1551. https://doi.org/10.1039/c3ee24455e

• Journal Article Type: Article
• Publication Date: May 1, 2013
• Deposit Date: May 14, 2013
• Publicly Available Date: Feb 11, 2014
• Journal: Energy & Environmental Science
• Print ISSN: 1754-5692
• Electronic ISSN: 1754-5706
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 6
• Issue: 5
• Pages: 1546-1551
• DOI: https://doi.org/10.1039/c3ee24455e
• Public URL: https://durham-repository.worktribe.com/output/1456232