(1. 河北大學(xué) 電子信息工程學(xué)院，保定 071002；
2. 河北大學(xué) 計(jì)算材料研究中心，保定 071002)
摘 要: 利用基于密度泛函理論的第一性原理超軟贗勢(shì)平面波方法對(duì)不同濃度P替位Ti摻雜銳鈦礦相TiO2的晶格參數(shù)、P電荷布居、能帶結(jié)構(gòu)、態(tài)密度和吸收光譜進(jìn)行計(jì)算。計(jì)算結(jié)果表明：隨著P摻雜濃度的增加，銳鈦礦相TiO2的晶胞體積逐漸減小，但摻雜P原子的電荷布居數(shù)基本沒(méi)有變化；同時(shí)禁帶寬度逐漸增大，并在價(jià)帶頂附近引入了摻雜能級(jí)，費(fèi)米能級(jí)進(jìn)入導(dǎo)帶，使TiO2呈現(xiàn)半金屬特性。隨著摻雜濃度的增大，摻雜TiO2在可見(jiàn)光區(qū)域吸收逐漸增強(qiáng)，同時(shí)吸收帶邊藍(lán)移程度逐漸增大。本研究中P摻雜銳鈦礦相TiO2禁帶寬度的計(jì)算結(jié)果與實(shí)驗(yàn)獲得的隨P摻雜濃度的提高TiO2禁帶寬度增大相一致。
關(guān)鍵字: 銳鈦礦相TiO2；P摻雜；第一性原理；電子結(jié)構(gòu)
（1. College of Electronic and Informational Engineering, Hebei University, Baoding 071002, China;
2. Research Center for Computational Materials，Hebei University, Baoding 071002, China）
Abstract:The lattice parameters, P charge populations, energy band structures, density of states and absorption spectra of anatase TiO2 doped with different concentrations of P substituting at Ti sites were calculated using the first-principles plane-wave ultra-soft pseudo-potential method based on the density functional theory. The calculated results show that with the increase of P doping concentration, the cell volume of the anatase TiO2 decreases, while the electronic populations of P keep almost unchanged. At the same time, the width of forbidden band gradually becomes larger, impurity levels are introduced near the valence band maximum，and the Fermi level goes into the conduction band, which makes that the TiO2 presents a half metal property. The absorption ability of TiO2 is gradually enhanced in the visible light region and the degree of the absorption edge blue shift becomes larger. The calculated forbidden band widths of the P-doped anatase TiO2 are consistent with the experimental results that, with the increase of P doping concentration, the forbidden band widths are enlarged.
Key words: anatase TiO2; P doping; first-principles; electronic structure
