Abstract CuNbO 3 is a promising semiconductor for photovoltaic and photo-electro-chemical conversion. To evaluate its potential, it is necessary to analyze the optical properties and quantify the main features when this material is used as an energy converter. To achieve this aim, first the optical properties are obtained using first-principles. The results, based on the split into contributions, show that the light absorption comes mainly from the p(O)-d(Nb) transitions of the NbO 6 octahedra. Later the absorption coefficients are used as criteria to evaluate photo-voltages, photocurrents and efficiencies of the solar conversion, and the effect of using total and partial solar spectrum ranges. Furthermore, we show that the efficiencies and photocurrents could be increased significantly using a multi-gap approach. Furthermore some voltage loss effects are analyzed.

中文翻译：

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CuNbO 3 作为太阳能转化为燃料和电力

摘要 CuNbO 3 是一种很有前途的光伏和光电化学转换半导体。为了评估其潜力，当这种材料用作能量转换器时，有必要分析其光学特性并量化主要特征。为了实现这一目标，首先使用第一性原理获得光学特性。基于贡献的拆分结果表明，光吸收主要来自 NbO 6 八面体的 p(O)-d(Nb) 跃迁。后来吸收系数被用作评估太阳能转换的光电压、光电流和效率以及使用总和部分太阳光谱范围的影响的标准。此外，我们表明使用多间隙方法可以显着提高效率和光电流。