A fatty acid photodecarboxylase-mimicking photonanozyme with defect-induced enzymatic substrate-binding pockets

Abstract

Hydrocarbon synthesis hints at the significance of in-depth investigations and detailed explanations of mimicking fatty acid photodecarboxylase (FAP). Considering the importance of photodecarboxylases in hydrocarbon synthesis, we present the potential of defective semiconductor nanomaterials as a novel type of photonanozymes (PNZs) that mimic enzyme-like performance, serving as alternatives to FAP. Ferrum-doped titanium dioxide (Fe-TiO₂) was synthesized to introduce appropriate amounts of surface defects including reduced Ti³⁺ sites and oxygen vacancies, which reduce the band gap of TiO₂ and enhance the visible-light absorption, thereby facilitating efficient charge trapping. Notably, the surface defects of Fe-TiO₂ PNZs singularly act as enzymatic substrate-binding pockets that enable efficient carboxylic acid adsorption during the dark process, conversely facilitating the formation of more defects and boosting the FAP-like activity for photocatalytic decarboxylation reactions. This work provides a creative strategy for designing substrate-dependent higher-concentration defects as enzyme-like binding sites on promising PNZs that mimic natural photoenzymes.

Keywords: Defect; Fatty acid photodecarboxylase; Oxygen vacancy; Photonanozyme; Titanium dioxide.