Ning Wan,Zipeng Xing,Junyan Kuang,Zhenzi Li,Junwei Yin,Qi Zhu,Wei Zhou
In-situ oxygen vacancy-mediated C-N-S-tridoped single crystal black TiO 2 (B) nanorods are smoothly manufactured. The sample preparation is divided into two steps, first of all, a simple hydrothermal process, followed by an in-situ solid-state chemical substitution method with calcination at 500 °C. We have a number of representations of the catalyst such as crystallinity, morphological structure, etc. by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and UV–vis diffuse reflectance spectroscopy, respectively. This b-C-N-S-TiO 2 (B) has the advantages of Oxygen Vacancy, single crystal structure of nanorods, Ti 3+ self-doping, C-N-S-tridoped, so this sample band gap is narrow. Moreover, through the reduction of phenol and Cr(VI), we know the photocatalytic performance of the b-C-N-S-TiO 2 (B), the reduction efficiency of phenol and Cr(VI) is ∼6.1 times and ∼7 times of no doping samples, respectively, under visible light illumination. The predominant photocatalytic performances because of the synergetic action of Ti 3+ self-doping, C-N-S-tridoped, oxygen vacancy, and the 1D single crystal B phase nanostructure, favoring the separation and transportation of photogenerated charge carriers and the visible light utilization.
In-situ C-N-S-tridoped single crystal black TiO 2 nanosheets with exposed {001} facets are successfully fabricated via a facile hydrothermal method combined with an in-situ solid-state chemical reduction approach, followed by calcination at 450 °C. The crystal structure, crystallinity, morphology and composition of the as-prepared samples are investigated through X-ray diffraction, Raman, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and UV–vis diffuse reflectance spectroscopy, respectively. The results suggest that the obtained C-N-S-tridoped single crystal black TiO 2 nanosheets exhibit uniform nanosheet-like structure with exposed {001} facets and average length of ∼300–400 nm, thickness of ∼20 nm. The visible-light photocatalytic degradation rate of methyl orange is up to 92.13%, and photocatalytic hydrogen evolution is 149.7 μmol h −1 g −1 . The excellent photocatalytic activity can be ascribed to the synergetic effect of surface heterojunction between {001} and {101} facets, the C-N-S-tridoping, and the formed Ti 3+ species in photocatalyst, which can not only favor the visible-light absorption but also facilitate the separation and transfer of photogenerated charges.