(齊齊哈爾大學(xué) 化學(xué)與化學(xué)工程學(xué)院，齊齊哈爾 161006)
摘 要: 應(yīng)用基于密度泛函理論的第一性原理平面波超軟贗勢(shì)方法研究N和Al單摻雜和共摻雜銳鈦礦相TiO2的電子結(jié)構(gòu)、能帶結(jié)構(gòu)、態(tài)密度及光學(xué)性質(zhì)。結(jié)果表明，摻雜后TiO2的晶格常數(shù)、原子間的鍵長、晶胞體積都發(fā)生了不同程度的變化；單摻雜和共摻雜均使得禁帶寬度減小，而且位于價(jià)帶和導(dǎo)帶之間的雜質(zhì)能級(jí)能夠捕獲由價(jià)帶躍遷至導(dǎo)帶的電子，減少光生載流子的復(fù)合率，提高TiO2的光催化性能；與單摻雜相比，共摻雜能級(jí)分裂較明顯，吸收光譜紅移幅度更大。
關(guān)鍵字: TiO2；N-Al共摻雜；能帶；第一性原理；態(tài)密度
（College of Chemistry and Chemical Engineering, Qiqihar University, Qiqihar 161006, China）
Abstract:The electronic structures of N-doped, Al-doped and N-Al co-doped anatase TiO2 were investigated by the first-principles plane wave ultra-soft pseudo-potential method based on the density functional theory (DFT). The crystal structures, energy bands, density of states (DOS) and optical properties were analyzed. The results indicate that the lattices, cell volumes of TiO2 and bond length of atoms of TiO2 after doping have different degrees of change. The band gap of single doped samples is narrowed as the same as the N-Al co-doped TiO2. Also the impurity energy levels appear near the Fermi level，which can reduce the recombination rates of photoexcited carriers, so, the photo catalysis efficiency of TiO2 is improved. The N-Al co-doped anatase TiO2 shows a stronger red-shift in the absorption edge than the single doped samples，and its energy level splitting is more obvious.
Key words: TiO2; N-Al co-doping; energy band; first-principles; states density
