中文摘要：

采用第一性原理计算方法详细研究了碳原子掺入WO3后体系的能带结构、态密度、导带边和价带边的位置的变化.考虑了碳原子处在间隙位置和碳原子替换氧原子两种情况.计算结果表明,碳原子替换氧原子时,体系是自旋极化的,在带隙中产生非常明显的C-2p杂质带.自旋向上部分带隙减小了0.92 e V,自旋向下部分带隙减小了0.08 e V.而碳处在间隙位置时,体系是非自旋极化的,碳原子倾向于与一个氧原子成键,带隙减小了0.2e V,有利于可见光的吸收.形成能计算表明,碳原子处在间隙位置掺杂更稳定.

英文摘要：

The properties of carbon doped WO3 are calculated by first principles calculations. The electronic structure, the valence band maximum and conduction band minimum are studied. Both carbon substituting oxygen atom or staying in the interstitial site are considered. The calculation results show that the system is spin polarized with carbon substituting oxygen atom and an impurity C-2p band emerges in the middle of the band gap. The band gap decreases by 0.92 eV for spin-up part and 0.08 eV for spin-down part. When the impurity carbon atom stays in the interstitial site, the system is unpolarized and the carbon atom prefers to bond one oxygen atom. The band gap decreases by 0.2 eV, which is beneficial for absorption of visible light. Formation energy calculation shows that the carbon atom prefers to site in the interstitial site rather than the substituting oxygen sites.