Waste valorization using solar energy offers a sustainable pathway to simultaneously address energy production and chemical manufacturing challenges. Dual-functional photocatalysis can “hit two birds with one stone” by coupling renewable hydrogen generation with the conversion of waste-derived feedstocks into value-added chemicals (Qi et al., 2021). Biomass is an important sustainable carbon source, and converting biomass-derived intermediates into high-value products through green technologies represents a promising strategy for advancing a circular chemical economy. Furfuryl alcohol is a key biomass-derived platform molecule that can be upgraded into furfural, a high-value chemical widely used in the fine chemical, polymer, and pharmaceutical industries (Han et al., 2017). To achieve this transformation while simultaneously producing renewable fuel, visible-light-active Ru-modified CdIn2S4 (Ru-CdIn2S4) nanosheets were synthesised via a solvothermal method with in-situ Ru incorporation and investigated as dual-functional photocatalysts (Hamza et al., 2024). The optimum Ru-CdIn2S4 photocatalyst achieved up to a 50-fold enhancement in hydrogen production compared with bare CdIn2S4. Simultaneously, the existence of Ru species improved the furfuryl alcohol conversion (from 39% to 61%) and furfural selectivity (from 58% to 77%). Mechanistic investigations supported by photoluminescence spectroscopy and density functional theory calculations revealed that Ru species act as charge-separation centres and catalytic sites that facilitate both proton reduction and selective alcohol oxidation. The enhanced performance was attributed to efficient transfer of photogenerated charge carriers to Ru species, promoting hydrogen evolution and favouring selective furfural formation. These findings highlight the potential of CdIn2S4-based photocatalysts for simultaneous green hydrogen production and waste valorization. Furthermore, CdIn2S4-based photocatalysts modified with various metal species, including ruthenium, gold, and platinum, have shown promise for coupling hydrogen production with benzylamine valorization into value-added nitrogen-containing compounds (Hamza et al., 2026) demonstrating promising broader applicability of dual-functional photocatalysis.
References
Hamza, M. A. et al. (2024) ‘Ultrathin Ru-CdIn2S4 nanosheets for simultaneous photocatalytic green hydrogen production and selective oxidation of furfuryl alcohol to furfural’, Chemical Engineering Journal, 493, p. 152603. doi: 10.1016/j.cej.2024.152603.
Hamza, M. A. et al. (2026) ‘Post‐Addition of Metal Species over CdIn2S4 Micro‐Pyramids/Nanosheets for Photocatalytic Hydrogen Production and Benzylamine Valorization’, Solar RRL, 10(7). doi: 10.1002/solr.202500933.
Han, G. et al. (2017) ‘Visible-Light-Driven Valorization of Biomass Intermediates Integrated with H2 Production Catalyzed by Ultrathin Ni/CdS Nanosheets’, Journal of the American Chemical Society, 139(44), pp. 15584–15587. doi: 10.1021/jacs.7b08657.
Qi, M. Y. et al. (2021) ‘Cooperative Coupling of Oxidative Organic Synthesis and Hydrogen Production over Semiconductor-Based Photocatalysts’, Chemical Reviews, 121(21), pp. 13051–13085. doi: 10.1021/acs.chemrev.1c00197.