Doped Anatase Titanium Dioxide Photocatalytic Properties Of The First-principles Calculation

Titanium dioxide as an oxide semiconductor material, has a very wide range of practical value. Its advantages are: raw materials, and more widely, the material itself has a strong stability and photocatalytic activity of the human body without harm to the photocatalytic material in preparation of people of all ages. In solar energy storage and utilization, air purification and sterilization, photochemical conversion, wastewater treatment, metals recovery and fog, and other aspects of self-cleaning surface has a wide range of applications. However, TiO2 photocatalytic also has a fatal defect, which is produced by electron-hole for easy compound to the photocatalytic activity is restricted.In order to improve its photocatalytic activity, which is to reduce the electron-hole pair of composite, the paper by first-principles density functional theory, using the modified method of doping elements in respect of non-metallic, transition metal elements, the concentration of calculation of single-factor experiments, concluded that the transition metal elements with non-metallic elements doped anatase TiO2 optimal concentration.Calculated that: incorporation of TiO2 in a typical non-metallic elements, N elements is the best mixed elements, while the concentration of doped N4 x 1 x 1 supercell when the optimal concentration, band gap of 1.592eV, the light response range extended to 380nm～537nm; incorporation of transition metals in TiO2, Cu element is the best mixed elements, the concentration of doped Cu4 x 1 x 1 supercell when the optimal concentration, band gap 1.14ev. TiO2unit cell and lattice distortion produced, the formation of oxygen vacancies, can better capture the photoelectron; eventually come to N-Cu-doped 4×1×1 supercell approach for the optimal doping, the band gap 1.083ev, with both N-doped region of the N-Cu absorption properties of Cu doped with oxygen vacancies and mechanism for greatly improving the overall performance of TiO2, the light response range 678nm, the actual change-doped anatase TiO2 nature provides a theoretical design.