Photocatalytic oxidative desulfurization with Anderson-type polyoxometalates nanoclusters doped carbon nitride

Photocatalytic oxidative desulfurization (PODS) presents a sustainable and cost-effective alternative to conventional diesel desulfurization techniques. In this study, various methodologies, including ultrasonic dispersion, sol-gel and impregnation, were employed to prepare Anderson-type polyoxometallates (POMs) (NH)4H6ZnMo6O24 derived ZnMo6/C3N4, composites for PODS. The photocatalytic properties of these composites were thoroughly characterized using various techniques. The synergistic effect between ZnMo6 nanoclusters and C3N4 sites significantly enhanced their photocatalytic activity in the visible light region. The incorporation of ZnMo6 increases the surface energy of C3N4 and enhances its electrons capture capacity, thereby reducing the electron-hole pair recombination rate and suppressing its photoluminescence intensity. Computational analysis reveals that the adsorption energy of dibenzothiophene (DBT) and charge transfer capacity are markedly enhanced upon ZnMo6 doping into C3N4. The optimized catalyst (50 % ZnMo6/C3N4) exhibited 100 % desulfurization rate with low catalyst dosage and O/S ratio within only 2 h. Importantly, negligible decay in performance is observed over five consecutive reuses, indicating its robust stability in PODS. This investigation provides a comprehensive model and theoretical framework for the multifunctional PODS system, demonstrating its potential for practical application.