Fabrication of novel direct Z-scheme + isotype heterojunction photocatalyst g-C3N4/TiO2 with peroxymonosulfate (PMS) activation synergy and 2D/0D structure

A novel strategy for fabricating C3N4/TiO2 Z-scheme heterojunctions based on C3N4 isotype heterojunctions is presented. This scheme exploits the structural plasticity of C3N4 to achieve a breakthrough in activity without adding new materials.

Highly crystalline anatase TiO2 nanocuboids as an efficient photocatalyst for hydrogen generation

Highly crystalline anatase titanium dioxide (TiO2) nanocuboids were synthesized via a hydrothermal method using ethylenediamine tetraacetic acid as a capping agent. The structural study revealed the nanocrystalline nature of anatase TiO2 nanocuboids. Morphological study indicates the formation of cuboid shaped particles with thickness of ∼5 nm and size in the range of 10-40 nm. The UV-visible absorbance spectra of TiO2 nanocuboids showed a broad absorption with a tail in the visible-light region which is attributed to the incorporation of nitrogen atoms into the interstitial positions of the TiO2 lattice as well as the formation of carbonaceous and carbonate species on the surface of TiO2 nanocuboids. The specific surface areas of prepared TiO2 nanocuboids were found to be in the range of 85.7-122.9 m2 g-1. The formation mechanism of the TiO2 nanocuboids has also been investigated. Furthermore, the photocatalytic activities of the as-prepared TiO2 nanocuboids were evaluated for H2 generation via water splitting under UV-vis light irradiation and compared with the commercial anatase TiO2. TiO2 nanocuboids obtained at 200 °C after 48 h exhibited higher photocatalytic activity (3866.44 μmol h-1 g-1) than that of commercial anatase TiO2 (831.30 μmol h-1 g-1). The enhanced photoactivity of TiO2 nanocuboids may be due to the high specific surface area, good crystallinity, extended light absorption in the visible region and efficient charge separation.

Antibacterial and photocatalytic activities of controllable (anatase/rutile) mixed phase TiO2 nanophotocatalysts synthesized via a microwave-assisted sol–gel method

TiO₂ with different ratios of anatase/rutile phases were synthesized via a microwave assisted sol–gel method and by applying a single source precursor (SSP) with a constant concentration of nitric acid that was used as the structure directing agent.

Electrochemical oxidation of 4-chlorophenol for wastewater treatment using highly active UV treated TiO2 nanotubes

In the present work, we report on a facile UV treatment approach for enhancing the electrocatalytic activity of TiO₂ nanotubes. The TiO₂ nanotubes were prepared using an anodization oxidation method by applying a voltage of 40 V for 8 h in a DMSO + 2% HF solution, and further treated under UV light irradiation. Compared with Pt and untreated TiO₂ nanotubes, the UV treated electrode exhibited a superior electrocatalytic activity toward the oxidation of 4-chlorophenol (4-ClPh). The effects of current density and temperature on the electrochemical oxidation of the 4-ClPh were also systematically investigated. The high electrocatalytic activity of the UV treated TiO₂ nanotubes was further confirmed by the electrochemical oxidation of other persistent organic pollutants including phenol, 2-, 3-, 4-nitrophenol, and 4-aminophenol. The total organic carbon (TOC) analysis revealed that over 90% 4-ClPh was removed when the UV treated TiO₂ electrode was employed and the rate constant was 16 times faster than that of the untreated TiO₂ electrode; whereas only 60% 4-ClPh was eliminated at the Pt electrode under the same conditions. This dramatically improved electrocatalytic activity might be attributed to the enhanced donor density, conductivity, and high overpotential for oxygen evolution. Our results demonstrated that the application of the UV treatment to the TiO₂ nanotubes enhanced their electrochemical activity and energy consumption efficiency significantly, which is highly desirable for the abatement of persistent organic pollutants.

Fabrication of Bi2S3/ZnO heterostructures: an excellent photocatalyst for visible-light-driven hydrogen generation and photoelectrochemical properties

Bi₂S₃/ZnO heterostructures were synthesized, showing a high catalytic effect in photocatalytic hydrogen generation and organic dye degradation under visible light.

Co2+ substituted La2CuO4/LaCoO3 perovskite nanocomposites: synthesis, properties and heterogeneous catalytic performance

Cobalt substituted La₂CuO₄/LaCoO₃ perovskite nanocomposites were prepared using a microwave combustion method.

Fabrication of a TiO2 trapped meso/macroporous g-C3N4 heterojunction photocatalyst and understanding its enhanced photocatalytic activity based on optical simulation analysis

The enhanced photocatalytic performance of a TiO₂ nanoparticle trapped meso/macroporous g-C₃N₄ heterojunction photocatalyst is strongly related to its enhanced light absorption as revealed by optical simulation.