Hierarchical 3C-SiC nanowires as stable photocatalyst for organic dye degradation under visible light irradiation

•High decolorization rate of methylene blue using hierarchical 3C-SiC nanowires was obtained.•The effect of methylene blue with different concentration to catalytic result was investigated.•The photocatalytic reaction mechanism of degrading methylene blue was explained.•The SiO2 layer generating on nanowire surface in the catalytic process was analyzed.

3C-SiC nanowires with hierarchical structure were synthesized by sol–gel carbothermal reduction method. The photocatalytic property of SiC nanowires was investigated. 3C-SiC hierarchical nanowires exhibited an enhanced photocatalytic activity by accelerating the photocatalytic degradation of methylene blue solution under visible light irradiation. Methylene blue was degraded efficiently after 5 h irradiation over the photocatalyst. The photocatalytic activity was affected by the initial concentration of the methylene blue solution. Silicon dioxide layer was observed on the surface of nanowires after the catalytic process. The positive effect of SiO2 surface oxygen vacancies and 3C-SiC hierarchical nanostructures on the high decolorization efficiency of SiC nanowires was discussed. The detailed photocatalytic redox processes were also explained.

Graphical abstractThe photocatalytic performance was enhanced by hierarchical nanostructural SiC nanowires due to the increased specific surface areas and efficient incident light scattering. The positive effect of SiO2 layer growth on the surface of nanowires during the catalytic process on the high decolorization efficiency of SiC nanowires was attributed to SiO2 surface oxygen vacancies.Figure optionsDownload full-size imageDownload as PowerPoint slide