COFfee: A Coffee Waste@Anthraquinone COF Nanocomposite as a Photocatalyst for Green Hydrogen Production

Sustainability is pivotal for the growth, development, and survival of future generations, necessitating a shift to renewable energy sources and sustainable materials. The development of waste-derived, visible-light-active, nontoxic photocatalysts for water splitting is a promising approach in this direction. We report the one-pot synthesis of a novel waste coffee (WC)-based covalent organic framework (COF) nanocomposite, WC@DqTp, via a vortex-assisted solvothermal method. Integrating an anthraquinone-based COF (DqTp) with WC enhances its photocatalytic performance through improved charge separation. The photocatalytic activity of WC@DqTp for hydrogen evolution from water using platinum as a co-catalyst without an added sacrificial agent (36.1 μmol g–1 h–1) was almost two times higher than that of bare COF DqTp (21.2 μmol g–1 h–1). XPS, photoelectrochemistry, and PL lifetime measurements demonstrated that the superior efficiency of the nanocomposite is likely due to the formation of a Z-scheme heterojunction between WC and DqTp. This work highlights the potential of sustainable materials as efficient photocatalysts for green hydrogen generation.