Constructing 1D/2D BiOI/ZnWO4 p-n heterojunction photocatalyst with enhanced photocatalytic removal of NO

BACKGROUND Photocatalysis technology based on green renewable solar energy has broad prospects in environmental protection and new energy utilization. The energy of the light can be utilized to convert the pollutants in the environment into non-toxic substances even available products. Due to its low cost and environmental protection, photocatalysis technology has been further developed in the fields of water splitting, sewage treatment and nitrogen oxides (NO (x)) removal. RESULTS In this study, zinc tungstate (ZnWO4) nanorods loaded on bismuth oxyiodide (BiOI) nanosheets with exposed {001} facet forming a 1D/2D BiOI/ZnWO4 p-n heterojunction photocatalysts were synthesized and their photocatalytic activities for nitric oxide (NO) removal were investigated. The 20% BOI/ZWO composite exhibited the most excellent photocatalytic NO removal performance, which were 32.32% and 48.24% under visible light and simulated sunlight irradiation, respectively. CONCLUSION A novel 1D/2D BiOI/ZnWO4 p-n heterojunction was successfully synthesized by a two-step procedure. Compared to the pure ZnWO4 and BiOI, the 20% BOI/ZWO composite has a significant increase in photocatalytic activity which is attributed to the enhanced visible light absorption and the improved separation of charge carriers. Trapping experiments and electron spin resonance results indicate that the hole (h (+)), super oxygen radical (center dot O-2(-)) and hydroxyl radical (center dot OH) play minor roles, while the electron (e (-)) has a major contribution to the NO removal process. Therefore, the BiOI/ZnWO4 p-n heterojunction is a promising material for NO removal. (c) 2020 Society of Chemical Industry