Photoconductivity as loss mechanism in organic solar cells

Journal article

We observe that the reverse current under illumination in solar cells containing C₆₀ and ZnPc is dominated by a photoshunt. This shunt, not present in the dark, causes a linear current-voltage relation under illumination showing no saturation. Although observable in bulk heterojunctions, this effect is more pronounced in the presence of a pristine C₆₀ layer. An internal quantum efficiency larger than unity under an applied negative voltage and in the spectral range where C₆₀ absorbs identifies charges which are injected in addition to those photogenerated. The photoshunt is also present in the power-generating region and represents a loss mechanism limiting the fill factor in particular for flat heterojunction devices. © 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim.

Authors: Tress, W; Leo, K; Riede, M

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Wiley
• Journal: Physica Status Solidi - Rapid Research Letters
• Volume: 7
• Issue: 6
• Pages: 401-405
• Publication date: 2013-06-01
• DOI: 10.1002/pssr.201307039
• EISSN: 1862-6270
• ISSN: 1862-6254
• Language: English
• Keywords: photoconductivity; photoshunt; internal quantum efficiency; organic solar cells