In2O3 nanocubes/carbon nanofibers heterostructures with high visible light photocatalytic activity

One-dimensional In2O3 nanocubes/carbon nanofibers (CNFs) heterostructures have been successfully obtained by a simple combination of electrospinning technique and solvothermal process for the first time. The as-obtained products were characterized by field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray (EDX) spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and IR spectra. The results revealed that the secondary In2O3 nanocubes were successfully grown on the primary CNF substrates. Photocatalytic tests displayed that the In2O3/CNFs heterostructures possessed a much higher degradation rate of rhodamine B (RB) than the pure In2O3 under visible light. The enhanced photocatalytic activity could be attributed to the formation of heterostructures, which might improve the separation of photogenerated electrons and holes. Moreover, the In2O3/CNF heterostructures could be easily recycled without the decrease of the photocatalytic activity due to their one-dimensional nanostructural property. The morphology of the secondary In2O3 nanostructures (nanocubes, nanoagglomerates or nanoparticles) could be controlled by adjusting the additives including CO(NH2)(2) and a defined amount of water. The general growth mechanisms for the In2O3 nanostructures have also been discussed.