Visible Active N-Doped TiO₂/WS₂ Heterojunction Nano Rods: Synthesis, Characterization and Photocatalytic Activity

Layered KTO/BiOCl nanostructures for the efficient visible light photocatalytic degradation of harmful dyes

Novel KTO/BiOCl nanostructured photocatalysts with various weight proportions were synthesized using a simple hydrothermal process. The as-prepared nanostructured composite catalysts were characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, UV-vis diffused reflectance spectroscopy, Raman spectroscopy, field emission scanning electron microscopy, transmission electron microscopy with high resolution, X-ray photoelectron spectroscopy, and photoluminescence (PL). The photocatalytic activity of prepared catalysts was examined using Rhodamine B (RhB) and Congo Red (CR) as the aimed pollutants. BiOCl nanoparticles were distributed uniformly on the surface of the K₂Ti₄O₉ nanobelts. The optical properties showed that the layered titanate with BiOCl nanostructured photocatalyst displayed improved photoresponsivity due to the narrowed bandgap. The PL results showed that the greater inhibition of the electron-hole recombination process and KTO/BiOCl with a mass proportion of 20% revealed the most favorable photocatalytic behavior. The rate constant of RhB and CR degradation was five times as high as that of the bare BiOCl and titanate. The superior photocatalytic performance was attributed to the advancement of heterojunction between the KTO nanobelt and BiOCl. The KTO/BiOCl nanostructure is a promising visible, active photocatalyst, and the photocatalytic mechanism is discussed using the possible band structures of BiOCl and KTO.

Morphology Control of TiO2 Nanorods Using KBr Salt for Enhancing the Photocatalytic Activity of TiO2 and MoS2/TiO2 Heterostructures

In this study, the effect of KBr salt on the growth of TiO₂ nanorods (NRs) was systematically studied. The addition of KBr with different concentrations provides a controllable growth of TiO₂ NRs using hydrothermal method. The results revealed that the presence of KBr molecules affects the growth rate by suppressing the growth in the lateral direction and allowing for axial growth. This results in affecting the morphology by decreasing the diameter of the nanorods, and increasing the free space between them. Enhancing the free spaces between the adjacent nanorods gives rise to remarkable increase in the internal surface area, with more exposure side surface. To obtain benefit from the enlargement in the inner surface area, TiO₂ NRs were used for the preparation of MoS₂/TiO₂ heterostructures. To study the influence of the morphology on their activity, TiO₂ NRs samples with different KBr concentrations as well as the MoS₂/TiO₂ heterostructures were evaluated towards the photocatalytic degradation of Rhodamine B dyes.

Degradation of Harmful Organics Using Visible Light Driven N-TiO₂/rGO Nanocomposite

Nitrogen doped titania over reduced form of graphene oxide (N-TiO₂/rGO) catalysts were synthesized by adopting single step hydrothermal route. All the prepared photocatalysts were thoroughly characterized by using different analytical tools such as XRD, Raman, UV-DRS, FE-SEM and HRTEM. The photocatalytic activities of bare and composite catalysts were evaluated towards the photocatalytic decolourisation/degradation of Methylene blue dye (MB) and Metronidazole antibiotic (MTZ) under visible electromagnetic radiation. Among all the synthesized catalysts, N-TiO₂/rGO composite catalyst showed the highest decolourisation/degradation activity towards both the dye and the antibiotic. The most active catalyst was also tested under UV and solar light irradiations which showed promising results. The stability of the most active catalyst (N-TiO₂/rGO) was examined by recyclability test. The possible photocatalytic mechanism was proposed for the composite catalyst.

Fabrication of a high-adsorption N–TiO2/Bi2MoO6 composite photocatalyst with a hierarchical heterostructure for boosted weak-visible-light photocatalytic degradation of tetracycline

TiO₂ hierarchical heterostructure photocatalyst was successfully fabricated through the in situ growth of Bi₂MoO₆ nanosheets on rough N–TiO₂ nanorods with a bark-like surface. The structure–property relationship of this composite material were researched.