Effect of doping TiO2 with alkaline-earth metal ions on its photocatalytic activity

Abstract

TiO 2 photocatalysts doped with alkaline-earth metal ions were prepared by the impregnation and coprecipitation methods. The sample were characterized by XRD, XPS and IR spectroscopy. Their activities were evaluated by the photocatalytic production of hydrogen. The activities of the doped photocatalysts dopended on the size of the dopant ions and the doping method. The optimum molar contents of dopant ions Be 2+ , Mg 2+ , Ca 2+ , Sr 2+ , Ba 2+ were 1.25, 1.25, 2.25, 2.25 and 2.25 at. %, respectively. The optimum calcination temperature and time were 400°C and 1 h.

Synthesis, characterisation, and effect of pH on degradation of dyes of copper-doped TiO2

“…[35] Second, due to the difference in the electron negativity between Ti and Cu, the TiÀOÀCu formed via Cu 2C entering into the shallow surface of TiO 2 could promote the charges to transfer, resulting in an increase of the photocatalytic activity. [36] Third, copper ion doping can cause a lattice deformation and produce defects in the crystal. The defects can inhibit the recombination of electron-hole pairs and enhances the activity.…”

“…The defects can inhibit the recombination of electron-hole pairs and enhances the activity. [36] However, when the content of copper ion was higher than its optimal level, an excess amount of copper ion could not diffuse into the TiO 2 lattice, but deposits on the surface of TiO 2 particles, leading to the hindrance of UV light penetration reaching the surface of TiO 2, which could block the active sites of TiO 2 and therefore inhibits the photocatalytic activity. [37] On the other hand, it was also reported in the literature that as the metal loading increases, agglomeration of metal particles is believed to occur and decrease the photocatalytic activity of photocatalyst.…”

Testing the antibacterial activity of doped TiO2 for preventing biodeterioration of cultural heritage building materials

“…In addition, silver ions are known to cause denaturation of proteins present in bacterial cell walls and slow down bacterial growth (Maness et al, 1999). Recently, alkaline-earth metal ions have been considered a promising, efficient and economic approach for doping the TiO 2 (Li et al, 2007). There are many reports on transition metal, rare earth and noble metal ion doping of TiO 2 , but studies on alkaline-earth metal ion doping of TiO 2 and their photocatalytic properties have rarely been reported.…”

Photocatalytic Performance of ZnS and TiO2Supported on AC Under Visible Light Irradiation

“…[24][25][26] In recent years, ZnS nanocrystals (NCs) have been extensively studied due to their unique properties and are reported to have potential as photocatalysts in environmental contaminant elimination, CO 2 reduction, and H 2 evolution. 27,28) For the sake of improving the photocatalytis efficiency of ZnS or TiO 2 , nanoscale ZnS coupled TiO 2 photocatalyst have attracted a great deal of attention for potential applications such as purification of water or organic dyes.…”