The investigation of CdS-quantum-dot-sensitized Ag-deposited TiO2 NRAs in photoelectrochemical hydrogen production

The synthesis of CdS/Ag/TiO2 for photoelectrochemical hydrogen production was carried out using electrochemical deposition and the SILAR method.

Electrospinning preparation of g-C3N4/Nb2O5 nanofibers heterojunction for enhanced photocatalytic degradation of organic pollutants in water

In this study, graphitic carbon nitride (g-C₃N₄) and niobium pentoxide nanofibers (Nb₂O₅ NFs) heterojunction was prepared by means of a direct electrospinning approach combined with calcination process. The characterizations confirmed a well-defined morphology of the g-C₃N₄/Nb₂O₅ heterojunction in which Nb₂O₅ NFs were tightly attached onto g-C₃N₄ nanosheets. Compared to pure g-C₃N₄ and Nb₂O₅ NFs, the as-prepared g-C₃N₄/Nb₂O₅ heterojunction exhibited remarkably enhanced photocatalytic activity for degradation of rhodamine B and phenol under visible light irradiation. The enhanced catalytic activity was attributed predominantly to the synergistic effect between g-C₃N₄ sheets and Nb₂O₅ NFs, which promoted the transferring of carriers and prohibited their recombination, confirmed by the measurement of transient photocurrent responses and photoluminescence spectra. In addition, the active species trapping experiments indicated that superoxide radical anion (·O₂^–) and hole (h⁺) were the major active species contributing to the photocatalytic process. With its high efficacy and ease of preparation, g-C₃N₄/Nb₂O₅ heterojunction has great potentials for applications in treatment of organic pollutants and conversion of solar energy.

Enhanced photocatalytic performance of WON@porous TiO2 nanofibers towards sunlight-assisted degradation of organic contaminants

In the last few decades, TiO₂ has been widely used in different types of photocatalytic applications. However, the relatively large optical band gap (∼3.2 eV), low charge carrier mobility and consequently its low quantum efficiency limit its photocatalytic activity. Herein, we construct a novel nanostructured heterojunction of WON/TiO₂ nanofibers (NFs) by integration of TiO₂ nanofibers synthesized by electrospinning of a polymer solution containing a titanium(iv) butoxide precursor with WON nanoparticles fabricated via annealing of a WO₃ precursor in dry ammonia at 700 °C. The synthesized photocatalysts were characterized using different spectroscopic techniques. Their photocatalytic performance towards the degradation of methyl orange, methylene blue, and phenol as model contaminants was investigated and the charge transfer process was elucidated and compared to that of a TiO₂/WO₃ heterojunction.

Coupling of WON with TiO₂ nanofibers creates a novel heterojunction with enhanced photocatalytic activity.