In Situ Generation of H₂O₂ over MoO_x Decorated on Cu₂O@CuO Core–Shell Particle Nanoarchitectonics for Boosting Photocatalytic Oxidative Desulfurization

Abstract

Photocatalytic oxidation desulfurization (PODS) has emerged as a promising, ecofriendly alternative to traditional, energy-intensive fuel desulfurization methods. Nevertheless, its progress is still hindered due to the slow sulfide oxidation kinetics in the current catalytic systems. Herein, we present a MoO x decorated on a Cu 2 O@CuO core−shell catalyst, which enables a new, efficient PODS pathway by in situ generation of hydrogen peroxide (H 2 O 2 ) with saturated moist air as the oxidant source. The photocatalyst delivers remarkable specific activity in oxidizing dibenzothiophene (DBT), achieving a superior rate of 7.8 mmol g −1 h −1 , while maintaining a consistent performance across consecutive reuses. Experimental investigations reveal that H 2 O 2 is produced through the two-electron oxygen reduction reaction (ORR), and both H 2 O 2 and the hydroxyl radicals ( • OH) generated from it act as the primary reactive species responsible for sulfide oxidation. Importantly, our catalyst accomplishes complete PODS of real diesel fuel, underscoring an appealing industrial prospect for our photocatalyst.

ZnIn2S4 Quantum Dot/Mo-Doped WO2.72 Nanowire Heterojunctions Boost the Photocatalytic Desulfurization of Diesel

“… As illustrated in the Nyquist plots (Figure b), the charge-transfer resistance of ZIS/Mo-WO 2.72 is inferior to that of WO 2.72 and Mo-WO 2.72 , in accord with the cyclic photocurrent diagrams (Figure c) . The significantly increased photocurrent intensity indicates that the doped Mo site and the decorated ZIS QDs can enhance the electron–hole separation and promote the generation of hot electron through the LSPR effect (Figure d). − …”