锐钛矿相和金红石相TiO_2：Nb的光电性能研究  

Electronic and optical properties of anatase and rutile TiO_2:Nb

作　　者：章瑞铄[1] 刘涌[1] 滕繁[1] 宋晨路[1] 韩高荣[1] 

机构地区：[1]硅材料国家重点实验室,浙江大学材料科学与工程学系,杭州310027

出　　处：《物理学报》2012年第1期392-396,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:51002135,51172200)资助的课题~~

摘　　要：采用基于密度泛函理论的第一性原理计算了锐钛矿相和金红石相TiO_2:Nb的晶体结构、电子结构和光学性质.结果表明,在相等的摩尔掺杂浓度下(6.25%),锐钛矿相TiO_2:Nb的导带底电子有效质量小于金红石相TiO_2:Nb,且前者室温载流子浓度是后者的两倍左右,即具有更大的施主杂质电离率,从而解释了锐钛矿相TiO_2:Nb比金红石相TiO_2:Nb具有更优异电学性能的实验现象.光学计算也表明锐钛矿相在可见光区有更大的透过率,从而在理论上解释了锐铁矿相TiO_2:Nb比金红石相'riO_2:Nb更适于做透明导电材料的原因.计算结果与实验数据能较好符合.First-principles calculations based on the density functional theory are used to study the crystal structure,electronic and optical properties of Nb doped anatase and rutile TiO_2.The calculated results reveal that anatase TiO_2：Nb has a smaller effective mass and carriers nearly twice lager than those of rutile TiO_2：Nb under the same doping concentration.And anatase TiO_2：Nb also exhibits a greater room-temperature ionization of donors.Besides,the calculated optical properties indicate that anatase TiO_2：Nb has a more excellent transparency than rutile TiO_2：Nb.All the results suggest that anatase TiO_2：Nb is more applicable to transparent conductive oxides.The calculated results consist well with the available experimental results.

关 键 词：TiO_2:Nb 第一性原理 电子结构 光学性能 

分 类 号：O73[理学—晶体学]