Ba₃(PO₄)₂ Photocatalyst for Efficient Photocatalytic Application

Barium phosphate (Ba₃(PO₄)₂) is a class of material that has attracted significant attention thanks to its chemical stability and versatility. However, the use of Ba₃(PO₄)₂ as a photocatalyst is scarcely reported, and its use as a photocatalyst has yet to be reported. Herein, Ba₃(PO₄)₂ nanoflakes synthesis is optimized using sol-gel and hydrothermal methods. The as-prepared Ba₃(PO₄)₂ powders are investigated using physicochemical characterizations, including XRD, SEM, EDX, FTIR, DRS, J-t, LSV, Mott-Schottky, and EIS. In addition, DFT calculations are performed to investigate the band structure. The oxidation capability of the photocatalysts is investigated depending on the synthesis method using rhodamine B (RhB) as a pollutant model. Both Ba₃(PO₄)₂ samples prepared by the sol-gel and hydrothermal methods display high RhB photodegradation of 79% and 68%, respectively. The Ba₃(PO₄)₂ obtained using the sol-gel process exhibits much higher stability under light excitation after four regeneration cycles. The photocatalytic oxidation mechanism is proposed based on the active species trapping experiments where O₂ ^•‒ is the most reactive species. The finding shows the promising potential of Ba₃(PO₄)₂ photocatalysts and opens the door for further investigation and application in various photocatalytic applications.