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[目的]研究Mn掺杂对锐钛矿TiO_2晶体可见光区催化活性的影响。[方法]采用基于密度泛函理论(DFT)框架下的第一性原理平面波赝势(PWPP)方法,研究掺杂对锐钛矿TiO_2晶体的晶体结构、能带结构、态密度的改变。同时我们也进行了Mn掺杂TiO_2的实验研究,从实验方面对掺杂后TiO_2光吸收性能变化进行研究。[结果]Mn掺杂TiO_2后,晶体的对称性和点群没有改变。通过对比纯TiO_2,Mn掺杂TiO_2的能带和态密度可以得出:Mn掺杂TiO_2后导带发生较大下移,且导带底部主要是Mn-3d的贡献,使禁带宽度变小,从而可见光吸收增强。实验结果也表明Mn掺杂后可见光吸收增强,和理论的红移结果一致。[结论]通过我们的计算和实验,说明Mn掺杂可以改善和提高TiO_2在可见光区的活性,这种材料具有很好的应用前景,值得做进一步的实验研究。
[Objective] The research aimed to study the influence of Mn doping on the photocatalytic activity in the visible region of anatase TiO_2. [Method] The first order principle plane wave pseudopotential (PWPP) method based on density functional theory (DFT) was used to study the crystal structure, energy band structure and density of state of doping anatase TiO_2 crystal. At the same time, we also carried out Mn-doped TiO 2 experimental study, from the experimental aspects of doped TiO 2 light absorption properties of the study. [Result] The crystal symmetry and point group did not change after Mn doped TiO2. By comparing the energy band and the density of states of pure TiO 2 and Mn-doped TiO 2, it can be concluded that the conduction band of Mn-doped TiO 2 shifts down a lot and the contribution of Mn-3d at the bottom of the conduction band decreases the band gap , So that visible light absorption is enhanced. The experimental results also show that visible light absorption increases after Mn doping, which is consistent with the theoretical redshift results. [Conclusion] Through our calculations and experiments, Mn doping can improve and enhance the activity of TiO_2 in the visible region. This material has good application prospects and deserves further experimental study.