Effect of ultraviolet radiation on organic photovoltaic materials and devices

Journal article

Organic photovoltaics are a sustainable and cost-effective power-generation technology that may aid the move to zero-emission buildings, carbon neutral cities, and electric vehicles. While state-of-the-art organic photovoltaic devices can be encapsulated to withstand air and moisture, they are currently still susceptible to light-induced degradation, leading to a decline in the long-term efficiency of the devices. In this study, the role of ultraviolet (UV) radiation on a multilayer organic photovoltaic device is systematically uncovered using spectral filtering. By applying long-pass filters to remove different parts of the UV portion of the AM1.5G spectrum, two main photodegradation processes are shown to occur in the organic photovoltaic devices. A UV-activated process is found to cause a significant decrease in the photocurrent across the whole spectrum and is most likely linked to the deterioration of the charge extraction layers. In addition, a photodegradation process caused by UV-filtered sunlight is found to change the micromorphology of the bulk heterojunction material, leading to a reduction in photocurrent at high photon energies. These findings strongly suggest that the fabrication of inherently photostable organic photovoltaic devices will require the replacement of fullerene-based electron transporter materials with alternative organic semiconductors.

Authors: Patel, J; Tiwana, P; Seidler, N; Morse, G; Lozman, O

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Chemical Society
• Journal: ACS Applied Materials and Interfaces
• Volume: 11
• Issue: 24
• Pages: 21543-21551
• Publication date: 2019-05-24
• Acceptance date: 2019-05-24
• DOI: 10.1021/acsami.9b04828
• EISSN: 1944-8252
• ISSN: 1944-8244
• Pmid: 31124649
• Language: English
• Keywords: photocurrent spectroscopy; electroluminescence spectroscopy; charge-transfer state; stability; external quantum efficiency