Constructing van der Waals (vdW) heterostructures by using different 2D materials is an effective strategy to overcome the shortcoming of single 2D materials. Recently, a novel 2D material boron selenide (BSe) has been predicted, holding a hexagonal structure similar to 2D transition metal dichalcogenides (TMDs). In this paper, the MoS₂/BSe, and WS₂/BSe heterostructures are therefore constructed, finding that they are type‐II band alignment semiconductors with bandgaps of 1.46 and 1.73 eV, respectively. Moreover, an indirect‐to‐direct bandgap transition, and a band alignment transition can be achieved by applying the perpendicular external electric fields to the vdW heterostructures. In addition, the two built heterostructures have a good optical absorption (10⁴), a broad optical absorption, and one competitive power conversion efficiencies (PCEs). The results also show that the PCE of the MoS₂/BSe heterostructures can be improved by increasing the number of BSe layers (11.63% for MoS₂–2BSe and 13.55% for MoS₂–3BSe). This study provides a practical way for BSe/TMDs vdW heterostructures in optoelectronic applications.

中文翻译：

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BSe / XS2（X = Mo，W）van der Waals异质结构的可调电子性质和潜在应用

通过使用不同的2D材料构造范德华（vdW）异质结构是克服单一2D材料缺点的有效策略。最近，已经预测了一种新型的2D材料硒化硼（BSe），其具有类似于2D过渡金属二卤化金属（TMDs）的六边形结构。因此，本文构建了MoS ₂ / BSe和WS ₂ / BSe异质结构，发现它们是带隙分别为1.46和1.73 eV的II型带取向半导体。此外，可以通过将垂直的外部电场应用于vdW异质结构来实现间接到直接的带隙跃迁和能带对准跃迁。此外，两个内置的异质结构具有良好的光吸收（10 ⁴），宽广的光吸收和一种具有竞争力的功率转换效率（PCE）。该结果还表明，在MOS的PCE ₂ / BSE异质结构可以通过增加BSE层（用于硫化钼11.63％的数量来提高₂为硫化钼-2BSe和13.55％₂ -3BSe）。这项研究为光电应用中的BSe / TMDs vdW异质结构提供了一种实用的方法。