Linking vertical bulk-heterojunction composition and transient photocurrent dynamics in organic solar cells with solution-processed MoOx contact layers

Tremolet de Villers, Bertrand J.; MacKenzie, Roderick C.I.; Jasieniak, Jacek J.; Treat, Neil D.; Chabinyc, Michael L.

Abstract

It is demonstrated that a combination of microsecond transient photocurrent measurements and fi lm morphology characterization can be used to identify a charge-carrier blocking layer within polymer:fullerene bulk-heterojunction solar cells. Solution-processed molybdenum oxide (s-MoO x ) interlayers are used to control the morphology of the bulk-heterojunction. By selecting either a low- or high-temperature annealing (70 C or 150 C) for the s-MoO x layer, a well-performing device is fabricated with an ideally interconnected, high-efficiency morphology, or a device is fabricated in which the fullerene phase segregates near the hole extracting contact preventing efficient charge extraction. By probing the photocurrent dynamics of these two contrasting model systems as a function of excitation voltage and light intensity, the optoelectronic responses of the solar cells are correlated with the vertical phase composition of the polymer:fullerene active layer, which is known from dynamic secondary-ion mass spectroscopy (DSIMS). Numerical simulations are used to verify and understand the experimental results. The result is a method to detect poor morphologies in operating organic solar cells.

Citation

Tremolet de Villers, B. J., MacKenzie, R. C., Jasieniak, J. J., Treat, N. D., & Chabinyc, M. L. (2014). Linking vertical bulk-heterojunction composition and transient photocurrent dynamics in organic solar cells with solution-processed MoOx contact layers. Advanced Energy Materials, 4(5), Article 1301290. https://doi.org/10.1002/aenm.201301290

• Journal Article Type: Article
• Acceptance Date: Oct 14, 2014
• Online Publication Date: Oct 24, 2013
• Publication Date: Apr 30, 2014
• Deposit Date: Oct 30, 2018
• Publicly Available Date: Oct 30, 2018
• Journal: Advanced Energy Materials
• Print ISSN: 1614-6832
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 4
• Issue: 5
• Article Number: 1301290
• DOI: https://doi.org/10.1002/aenm.201301290
• Public URL: https://nottingham-repository.worktribe.com/output/1210938
• Publisher URL: https://onlinelibrary.wiley.com/doi/abs/10.1002/aenm.201301290
• Contract Date: Oct 30, 2018