第一性原理计算N掺杂对InNbO4电子结构的影响

宽带隙（3.83 eV）半导体光催化材料InNbO4在紫外光作用下具有分解水和降解有机物的性能。最近实验发现了N掺杂InNbO4具有可见光下分解水制氢的活性。为了从理论上解释这一实验现象，本文采用基于密度泛函理论的第一性原理计算了N掺杂对InNbO4的能带结构、态密度和光学性质的影响。分析能带结构可得，N掺杂后在InNbO4的价带（O 2p）上方形成N 2p局域能级，导致电子跃迁所需的能量减小。吸收光谱表明，N掺杂后InNbO4的光吸收边出现了红移，实现了可见光吸收。

N doping influences on electronic structure of InNbO4 from first-principle calculations

Indium niobate (InNbO4), as a wide band gap (3.83 eV) photocatalyst, could split the water and decompose the organic compounds under UV light irradiation. Recently, nitrogen doping InNbO4 was prepared and exhibited the photocatalytic activity of hydrogen generation upon visible light irradiation. In order to explain this phenomenon, the geometry structure, density of states and optical properties of N doped InNbO4 were investigated by first-principles method based on the density function theory. The calculated band structures indicated that some N 2p states were located above the valance band, which led to the reduction of the electron transition energy. The absorption spectra showed that the N-doped InNbO4 shifted its absorption edge from UV region to visible light region.