Kettle, JeffWaters, HuwHorie, MasakiSmith, Graham C.2016-03-072016-03-072016-01-27Kettle, J., Waters, H., Horie, M., Smith, Graham C. (2016). Alternative selection of processing additives to enhance the lifetime of OPVs. Journal of Physics D: Applied Physics, 49(8). DOI: 10.1088/0022-3727/49/8/08560110.1088/0022-3727/49/8/085601http://hdl.handle.net/10034/600689The use of processing additives is known to accelerate the degradation of Organic Photovoltaics (OPVs) and therefore, this paper studies the impact of selecting alternative processing additives for PCPDTBT:PC71BM solar cells in order to improve the stability. The use of naphthalene-based processing additives has been undertaken, which is shown to reduce the initial power conversion efficiency by 23%-42%, primarily due to a decrease in the short-circuit current density, but also fill factor. However, the stability is greatly enhanced by using such additives, with the long term stability (T50%) enhanced by a factor of four. The results show that there is a trade-off between initial performance and stability to consider when selecting the initial process additives. XPS studies have provided some insight into the decreased degradation and show that using 1-chloronaphthalene (ClN) leads to reduced morphology changes and reduced oxidation of the thiophene-ring within the PCPDTBT backbone.enorganic photovoltaicssolar cellsdegradationXPSArticle1361-6463Journal of Physics D: Applied Physics