Construction of a BiOI/g-C3N4 heterojunction photocatalyst: visible light-mediated efficient and selective oxidation of 5-hydroxymethylfurfural†

Abstract

The escalating demand for sustainable energy has intensified the search for photocatalysts capable of harnessing solar energy for chemical conversions, with a particular focus on non-noble metal catalysts. This study presents the synthesis of a novel BiOI/g-C₃N₄ heterojunction photocatalyst via an ultrasound-assisted co-precipitation method, demonstrating its efficiency in the visible light-mediated oxidation of 5-hydroxymethylfurfural (HMF) to 5-hydroxymethyl-2-furancarboxylic acid (HMFCA). The innovative synthesis approach ensures a well-crystallized and uniformly dispersed composite, critical for optimizing photocatalytic performance. By meticulously adjusting the composite ratio, this study fine-tunes the electronic structure and optoelectronic properties, enhancing light absorption and charge carrier dynamics. The BiOI/g-C₃N₄ photocatalyst achieved a maximum HMFCA yield of 43.6% and selectivity of 68.1% under visible light irradiation, showcasing its potential for sunlight-driven biomass conversion. Moreover, the catalyst exhibited excellent stability and reusability, retaining performance after five recycling cycles with only a 6.6% decrease in HMFCA yield. This work not only advances the understanding of non-noble metal photocatalysts for sustainable biomass conversion but also aligns with the principles of green chemistry by employing a renewable resource-based approach and minimizing environmental impact.