Solar-to-H2O2 Energy Conversion by the Photothermal Effect of a Polymeric Photocatalyst via a Two-Channel Pathway

With a view to using solar energy, the exploitation of near-infrared (NIR) light, which constitutes about 50 % of solar energy, in photocatalytic H₂O₂ synthesis remains challenging. In this study, resorcinol−formaldehyde (RF), which has a relatively low bandgap and high conductivity, is introduced for photothermal catalytic generation of H₂O₂ under ambient conditions. Owing to the promoted surface charge transfer rate under high temperature, the photosynthetic yield reaches roughly 2000 μm within 40 min under 400 mW cm⁻² irradiation with a solar-to-chemical conversion (SCC) efficiency of up to 0.19 % at 338 K under ambient conditions, exceeding the rate of photocatalysis with a cooling system by a factor of about 2.5. Notably, the H₂O₂ produced by RF during photothermal process was formed via a two-channel pathway, leading to the overall promotion of H₂O₂ formation. The resultant H₂O₂ can be applied in situ for pollutant removal. This work offers a sustainable and economical route for the efficient formation of H₂O₂.