The effects of chemical bond relaxation on the electronic and optical perproties of doped TiO2

• 作 者: C.Li;Y.F.Zhao;Y.Y.Gong;T.Wang;C.Q.Sun;
• 机 构: Center for Coordination Bond Engineering,College of Materials Science and Engineering,China Jiliang
• 出 处: 2014第二届中国网络安全大会
• 发表日期: 2014年期

　　As the semiconductor photocatalyst,the influences of impurities on the band gap value of TiO2 have been widely researched.However,the effects of chemical bonds on its electronic and optical properties have not been analyzed systematically.In this paper,the first principles calculations were carried out on anatase TiO2 systems doped with early TM(group III-B = Sc,Y and La; group IV-B = Zr and Hf; group V-B = V,Nb and Ta).Doping with transition metals results in the chemical bond relaxation,and the percentage of covalent bond part in TM-O bonds have also been altered,the Mulluken bond population(MP)values directly reflect the strength of the hybrid orbital of TM–O bonding.Results shown that band gap increases approximately linearly with the MP value.The less the percentage of covalent bond part in TM-O bonds,the smaller the band gap value of the TM doped TiO2,and the optical absorption edge redshift.