Stimuli-Responsive Luminescent Solar Concentrators Based on Photoreversible Polymeric Systems

Luminescent solar concentrators (LSCs) consist of dye-doped, highly transparent, plastic plates aimed at improving the building integration and reducing the cost of photovoltaic (PV) technology. In the thin-film configuration, the surface of these devices is particularly exposed to mechanical damage and to a consequent loss of performance in terms of power conversion. To address this issue, the first demonstration of a healable thin-film LSC based on a photoreversible polymer network as the host matrix is presented in this work. The photoresponsive matrix is obtained by simple UV curing of a coumarin functional polyurethane through reversible [2+2] cycloaddition. The final cross-linked coating is optically clear and exhibits excellent scratch remendability after suitable UVC/UVA exposure. The LSC devices obtained by doping the responsive matrix with perylene- or coumarin-based organic dyes possess a remarkable PV performance, comparable with control devices based on poly­(methyl methacrylate). The loss of performance induced by surface mechanical scratches can be fully recovered by UV irradiation, as a result of the photoreversibility of the coumarin functional polymer network. The healing strategy presented here, purely light-triggered, expands the tools for the design of durable and responsive thin-film LSCs.