Solvent-based revival of carbon-based perovskite solar cells

Perovskite solar cells (PSCs) combine high efficiency with low-cost processing, but their rapid progress toward commercialization is challenged by insufficient end-of-life strategies. Here we present the proof-of-concept of solvent-based revival of carbon-based PSCs using the green solvent γ -valerolactone (GVL) reaching high revival rates, which requires significantly less energy compared to the production of a new device. With this revival approach, we not only recover the materials but also the structure of the whole devices, including the energy and costs invested in them in the original manufacturing, thus advancing the highest level of resource-efficient recycling within the eco-design concept. Devices subjected to the optimized protocol revived up to 95% of their initial power conversion efficiency, with a stable fill factor and only modest reductions in photocurrent and open-circuit voltage ( V oc ). Impedance spectroscopy revealed only a small increase in series and charge-transfer resistances, attributable to interfacial changes of the carbon/perovskite boundary, while scanning electron microscopy confirmed the preservation of the carbon scaffold and successful reinfiltration of the perovskite precursor. Energy return on investment analysis further highlighted the sustainability advantage of revival compared to single-use devices. These results establish GVL-assisted revival as a practical first-level recycling strategy for PSCs.