<i>m</i>-Guaiacol-Derived Benzoxazine Resins as Surprising Heterogeneous Photocatalysts for the Photocatalytic Production of Hydrogen Peroxide under Visible Light

Semiconductors harness the power of light to conduct molecular transformations, enabling photocatalytic fuel synthesis, including hydrogen peroxide from molecular oxygen. Despite well-documented performances, the dependence on critical raw materials in semiconducting particles raises doubts regarding the sustainability of photocatalytic processes. In recent years, there has been an emerging trend to utilize organic semiconductors, including covalent organic frameworks and carbon nitrides as heterogeneous photocatalysts; however, their scalability, synthetic conditions, and synthesis temperatures hamper widespread availability. Benzoxazine resins are cross-linked thermosetting resins mainly studied as potential replacements for epoxy resins. In this work, photocatalytic hydrogen peroxide production employing benzoxazines as heterogeneous metal-free polymeric photocatalysts is monitored, and fuel production efficiency by means of chemical structure and curing is studied. Cured aromatic benzoxazine affords a higher fuel production performance, compared to linear or uncured analogues.