BiOBr/g-C3N4 heterojunction photocatalyst: Efficient benzyl alcohol oxidation without additional oxidants

A heterojunction of bismuth oxybromide (BiOBr) and graphitic carbon nitride (g-C 3 N 4 ) was synthesized via an in situ deposition method for the selective photocatalytic oxidation of benzyl alcohol to benzaldehyde without the need for additional oxidants. The optimized BiOBr/g-C 3 N 4 (2:1) sample demonstrated a significant enhancement in benzaldehyde production (36.08 %) compared to pure g-C 3 N 4 (15.48 %), with improved selectivity (64.06 % compared to 29.66 % for g-C 3 N 4 ) under mild conditions (atmospheric pressure, 20°C). Structural and photoelectric property analyses, along with DFT calculations, revealed the synergistic interactions between the two components, elucidating the charge transfer mechanism and the role of the S-scheme heterojunction in enhancing photocatalytic performance. Free-radical-capture experiments identified electrons (e-) and holes (h+) generated within the BiOBr/g-C 3 N 4 system as the primary reactive species responsible for the oxidation of benzyl alcohol. This study demonstrates the potential of the BiOBr/g-C 3 N 4 composite as an advanced photocatalyst for chemical transformations, showcasing its effectiveness without the need for additional oxidants.