Weixin Huang

Construction of Heterostructured g-C3N4/Ag/TiO2 Microspheres with Enhanced Photocatalysis Performance under Visible-Light Irradiation

The visible-light photocatalytic performance of the heterostructured g-C3N4/Ag/TiO2 microspheres was investigated. As an electron-conduction bridge, Ag nanoparticles were photodeposited as the interlayer between g-C3N4 and the surface of TiO2 microspheres to increase visible-light absorption via the surface plasmon resonance. The interface between Ag/TiO2 and g-C3N4 facilitates the direct migration of photoinduced electrons from g-C3N4 to Ag/TiO2, which is conductive to retarding the recombination of electron-holes. The g-C3N4 (4%)/Ag/TiO2 microsphere sample shows significant photocatalytic activity, higher than the sum of g-C3N4 (1.2 mg) and Ag/TiO2 samples, or the sum of TiO2 and Ag/g-C3N4 (1.8 mg) samples. It indicates that the heterostructured combination of g-C3N4, Ag and TiO2 microspheres provides synergistic photocatalytic activity through an efficient electron transfer process.

Superhydrophilic nano-TiO2 film with porous surface structure

Abstract The TiO2 films prepared from a sol–gel precursor were deposited on glass substrates using spin coating technique. Titania sols were doped with and without a pore generating agent, polyethylene glycol (PEG), to evaluate the effect of porosity on the superhydrophilicity of the coatings. The crystalline phase and surface morphology of the TiO2 thin films were characterised by XRD, SEM and scanning measurement station (SMS). Wetting behaviour of the resulting films were characterised using contact angle measurements. This particular porous surface prepared from 0·5M tetrabutyl titanate with PEG sintered at 450°C was in anatase form and has maximum specific surface area and average roughness. The results show that the PEG doped anatase TiO2 film exhibits superhydrophilic characteristic, although it is not exposed to ultraviolet irradiation. Finally, the formation mechanism and the property–structure relationship were discussed in detail.