Chemoenzymatic Photoreforming: A Sustainable Approach for Solar Fuel Generation from Plastic Feedstocks

Abstract

Plastic upcycling through catalytic transformations is an attractive concept to valorize waste, but the clean and energy-efficient production of high-value products from plastics remains challenging. Here, we introduce chemoenzymatic photoreforming as a process coupling enzymatic pretreatment and solar-driven reforming of polyester plastics under mild temperatures and pH to produce clean H₂ and value-added chemicals. Chemoenzymatic photoreforming demonstrates versatility in upcycling polyester films and nanoplastics to produce H₂ at high yields reaching ∼10³-10⁴ μmol g_sub^-1 and activities at >500 μmol g_cat^-1 h^-1. Enzyme-treated plastics were also used as electron donors for photocatalytic CO₂-to-syngas conversion with a phosphonated cobalt bis(terpyridine) catalyst immobilized on TiO₂ nanoparticles (TiO₂|<b>CotpyP</b>). Finally, techno-economic analyses reveal that the chemoenzymatic photoreforming approach has the potential to drastically reduce H₂ production costs to levels comparable to market prices of H₂ produced from fossil fuels while maintaining low CO₂-equivalent emissions.