The first-principles calculations based on density functional theory (DFT) have been realized to study electronic, optical, and photocatalytic properties of the wolframite InNbO₄ and InTaO₄ compounds. In order to clarify the question of the valance-to-conduction bandgap of the pristine compounds, still debated in the literature, a series of recently developed exchange and correlation (XC) potentials have been employed, besides the standard generalized gradient approximation. It was concluded that the Becke-Johnson (BJ) potential has been the most successful, resulting in bandgap values of 3.71 eV and 4.20 eV for the InNbO₄ and InTaO₄ respectively, in agreement with recent experimental studies. By employing this XC potential, the electronic structure and optical properties of both compounds have been calculated and analyzed. A good agreement of the calculated reflectivity and absorption spectra with available experimental data assures that the DFT approach with BJ XC potential correctly describes the electronic properties of InNbO₄ and InTaO₄. Their photocatalytic efficiencies have been analyzed by calculating band-edge positions with respect to the H⁺/H₂ reduction, and O₂/H₂O oxidation potential. It was concluded that both compounds exhibit band alignments suitable for efficient water splitting photocatalysis. However, due to their large bandgaps, the pristine materials should contain intrinsic and/or extrinsic defects to absorb in visible part of the solar spectrum.

已经实现了基于密度泛函理论 (DFT) 的第一性原理计算来研究黑钨矿 InNbO ₄和 InTaO ₄化合物的电子、光学和光催化性能。为了澄清原始化合物的价传导带隙问题，在文献中仍然存在争议，除了标准的广义梯度近似外，还采用了一系列最近开发的交换和相关 (XC) 势。得出的结论是，贝克-约翰逊 (BJ) 势能最成功，导致 InNbO ₄和 InTaO _{4 的}带隙值为 3.71 eV 和 4.20 eV分别与最近的实验研究一致。通过使用这种 XC 电位，计算和分析了两种化合物的电子结构和光学性质。计算的反射率和吸收光谱与可用实验数据的良好一致性确保了具有 BJ XC 电位的 DFT 方法正确描述了 InNbO ₄和 InTaO ₄的电子特性。通过计算相对于 H ⁺ /H ₂还原和 O ₂ /H _{2 的}带边位置来分析它们的光催化效率O氧化电位。得出的结论是，这两种化合物都表现出适合高效水分解光催化的能带排列。然而，由于它们的大带隙，原始材料应包含内在和/或外在缺陷以吸收太阳光谱的可见光部分。