In situ growth of flower sphere Bi2WO6/Bi-MOF heterojunction with enhanced photocatalytic degradation of pollutants: DFT calculation and mechanism

The construction of heterojunctions is an optimal strategy to achieve efficient charge separation and enhance photocatalytic performance. Hence, the flower sphere-like Bi2WO6/Bi-MOF heterojunction were fabricated by in situ growth method of Bi2WO6 on Bi-MOF, and the photocatalytic degradation of pollutants under visible light irradiation was conducted to evaluate their photocatalytic performance. The optimized Bi2WO6/Bi-MOF-0.4 photocatalyst exhibited high photocatalytic activity. The degradation efficiencies of Rhodamine B (RhB) and tetracycline hydrochloride (TC) were 96 % and 80 % within 60 min of light irradiation respectively. The superior photocatalytic activity can be ascribed to the constructed type II heterojunction interface between Bi-MOF and Bi2WO6, which significantly accelerated the separation efficiency of interface charges. The possible mechanism for photocatalytic degradation of the pollutant was proposed by Electron paramagnetic resonance (EPR) and band structure. In addition, the degradation pathways of intermediates during photodegradation were investigated by liquid chromatography analysis with mass spectrometry (LC-MS).

Automated summary

The construction of heterojunctions is an effective approach to achieve efficient charge separation and enhance photocatalytic performance. In this study, flower sphere-like Bi2WO6/Bi-MOF heterojunctions were successfully fabricated, and their photocatalytic activity under visible light irradiation was evaluated. The optimized Bi2WO6/Bi-MOF-0.4 photocatalyst exhibited high photocatalytic activity, with degradation efficiencies of 96% for Rhodamine B and 80% for tetracycline hydrochloride within 60 minutes. The enhanced photocatalytic activity can be attributed to the type II heterojunction interface between Bi-MOF and Bi2WO6, which promotes the efficient separation of interface charges. The possible mechanism of photocatalytic degradation was proposed using Electron paramagnetic resonance (EPR) and band structure, and the degradation pathways of intermediates were investigated using liquid chromatography-mass spectrometry (LC-MS) analysis.