Abstract Bulk transition metal dichalcogenides are indirect gap semiconductors with optical gaps in the range of 0.7–1.6 eV, which makes them suitable for solar cell applications. In this work, we study the electronic structure, optical properties, and the thickness dependence of the solar cell efficiencies of MX2 (M: Mo, W; X: S, Se, Te) with density functional theory and GW + BSE. Through this analysis, we find a change in solar cell efficiency trends at slab thicknesses of 3 μm. For thin films solar cells (thicknesses smaller than 3 μm), the tellurides present the highest efficiencies (about 20% for a 100 nm thick slab). In contrast, for thicknesses greater than 3 μm, our results indicate that a maximum solar cell efficiency can be achieved in WS2. For instance, a 100 μm slab of WS2 presents a solar cell efficiency of 36.3%, making this material a promising candidate for solar cell applications.

中文翻译：

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过渡金属二硫属化物 MX2 中太阳能电池效率的厚度依赖性（M：Mo、W；X：S、Se、Te）

摘要 块状过渡金属二硫属化物是光学间隙在 0.7-1.6 eV 范围内的间接间隙半导体，适用于太阳能电池应用。在这项工作中，我们利用密度泛函理论和 GW + BSE 研究了 MX2（M：Mo，W；X：S，Se，Te）太阳能电池效率的电子结构、光学特性和厚度依赖性。通过这一分析，我们发现了 3 μm 厚板时太阳能电池效率趋势的变化。对于薄膜太阳能电池（厚度小于 3 μm），碲化物表现出最高的效率（对于 100 nm 厚的平板约为 20%）。相比之下，对于大于 3 μm 的厚度，我们的结果表明在 WS2 中可以实现最大的太阳能电池效率。例如，一块 100 μm 的 WS2 板的太阳能电池效率为 36.3%，