Design and Application of Wide-Angle Ultraviolet Stop Filter for Semi-transparent Organic Photovoltaics

The threat of global warming can be mitigated by converting from fossil fuels to green energy sources to power our economies. Semi-transparent organic photovoltaics (ST-OPVs) provide an opportunity to do so. These devices present a unique solution to the clean energy challenge from their capabilities of being transparent, lightweight, flexible, and easily producible for window integrated applications. However, there are concerns about their operational longevity. Research has shown that one of the failure modes that lessens the lifetime of these devices is degradation of the active layer¹ by high energy ultraviolet (UV) radiation. Radiation in this band breaks the bonds within organic molecules that form the device photoactive layers. We report on the design and implementation of a modified substrate that serves the dual functions of blocking UV radiation and reducing Fresnel reflections at the light incident side of the device to extend the lifetime and reduce losses in the power conversion efficiency (PCE).