Study on the micro-mechanism of Pt-doped anatase TiO_2

The crystal structures,electronic structures and optical properties of platinum-doped anatase TiO2 were calculated by first principles with plane-wave ultrasoft pseudopotential approach.The calculated results show that the lattice is distorted,the crystal cell volume and the octahedral dipole moments are increased;the impurity level both at the valence band top and the conduction band bottom are formed by Pt 5d orbit level with O 2p and Ti 3d orbit level hybridization which resulted in the energy gap narrowed and the red-shift of the light absorption wavelength.The theoretical calculation results are consistent with that of the experiment study reported,and give a good mechanism interpretation to the photocatalytic activity enhancement Pt-doped anatase TiO2.