Pt-N共掺杂锐钛矿TiO_2的第一性原理研究

采用基于密度泛函理论(DFT)的第一性原理中的平面波超软赝势(PWPP)方法对理想TiO_2,N单掺杂,Pt单掺杂和Pt-N共掺杂锐钛矿相TiO_2的电子结构进行计算,分析N单掺杂、Pt单掺杂及Pt-N共掺杂对锐钛矿相TiO_2的晶体结构、能带和态密度的影响.计算结果表明:掺杂后TiO_2的晶格发生畸变,原子间键长的变化使晶格发生膨胀,Pt单掺杂、N单掺杂TiO_2禁带宽度变窄,Pt-N共掺杂TiO_2分别在价带顶和导带底产生杂质能级,且禁带宽度缩小范围大,表明Pt-N共掺杂能进一步提高锐钛矿TiO_2催化性能.

First-principles study on Pt-N co-doped anatase TiO2

The electronic structures of N-doped, Pt-doped and Pt-N co-doped anatase TiO2 were calculated by the first-principles plane wave ultra-soft pseudo-potential method based on the density functional theory (DFT). The effects of doping on crystal structures, energy bands and density of states (DOS) were analyzed. The calculation results show that, after doping the lattices of TiO2 are distorted by the doping and the bond length change of atoms leads to the lattice expansion, N-doped TiO2, Pt doped TiO2, forbidden band width narrowing, Pt-N co-doped TiO2 at the top of the valence band and the bottom of the conduction band respectively produce the impurity level, and narrow band gap width is greater, suggest that Pt - N co-doped can further improve the anatase TiO2 photo catalytic performance.