Photoreforming of solid waste on 1 m2 scale using single-source precursor-derived co-catalyst films.

Abstract

Photocatalytic reforming offers a route to valorize biomass and plastic waste into clean H2 under ambient conditions. However, the scalability of photocatalyst sheets is limited by high-temperature processing, binders and complex co-catalyst deposition. Here a [Co4Zr2O(O n Pr)10(acac)4] single-source precursor is deposited onto Al-doped SrTiO3 and immobilized on glass substrates to fabricate photocatalyst sheets using multiple techniques, including high-throughput spray coating. The resulting sheets enable photoreforming of cellulose- and polyethylene terephthalate-derived feedstocks, producing H2 alongside value-added organics such as formate, acetate, glycolate and glycolaldehyde dimer. The system is demonstrated from the centimeter- to meter-squared scale, culminating in a 1-m2 outdoor reactor operating under natural sunlight. After 6 h, H2 yields reached 5.24 and 1.51 mmol m-2 for glucose and pretreated cellulose, respectively, with concurrent formation of oxygenates. Techno-economic analysis based on real-world data estimates an H2 cost of £0.93 mmol-1. This work advances scalable photocatalytic reforming and provides a step towards practical deployment.