Efficient degradation of bentazone via peroxymonosulfate activation by 1D/2D γ-MnOOH-rGO under simulated sunlight: Performance and mechanism insight

An innovative 1D/2D γ-MnOOH-rGO catalyst was successfully synthesized by anchoring γ-MnOOH nanowires on rGO nanosheets. Its catalytic activity was comprehensively evaluated by bentazone degradation in PMS/simulated sunlight system. Results showed that the γ-MnOOH-rGO catalyst achieved 96.1% decomposition of bentazone within 90 min in the coupled system, improving by 26.7% compared to that obtained in the γ-MnOOH mediated system. Moreover, the newly-designed γ-MnOOH-rGO exhibited stability, recyclability and practicability for bentazone elimination. Mechanism insight highlighted that more active sites exposed on γ-MnOOH-rGO surface, providing more opportunities for PMS activation and bentazone degradation. Besides, the rGO could transfer photo-induced electrons, accelerating radical-based reactions. More importantly, ∙OH and 1O2 appeared in γ-MnOOH-rGO/PMS/simulated sunlight system, which played an overwhelming role in bentazone removal. In prospect, the γ-MnOOH-rGO showed promising potential for refractory contaminants remediation from aquatic environment in PMS/photocatalytic system.