Electronic and optical properties of monolayer tungsten selenide \((\text {WSe}_2)\) and cadmium zinc telluride \((\text {Cd}_{0.9}\text {Zn}_{0.1}\text {Te})\) heterostructure with VdW, i.e., Van der Waals attractions between two layers, are explored using first-principles calculations. From the results, it is discovered that the proposed heterostructure of \(\text {WSe}_2/\text {Cd}_{0.9}\text {Zn}_{0.1}\text {Te}\) results into nearly direct band gap semiconducting material and has staggered (Type-II) band gap alignment which is required for opto electronic applications. Moreover, the results suggest that for monolayer \(\text {WSe}_2\) and \(\text {Cd}_{0.9}\text {Zn}_{0.1}\text {Te}\), optical absorption is significant in a limited range of visible spectrum (\(\approx\) 420–470 nm) and (\(\approx\) 390–430 nm), respectively, but more absorption takes place in the infrared (IR) region for individual layers. However, the absorption in the \(\text {WSe}_2/\text {Cd}_{0.9}\text {Zn}_{0.1}\text {Te}\) heterostructure results in the red shift phenomenon and high absorption is achieved in the entire visible spectrum (\(\approx\) 410–710 nm). Along with the absorption spectrum, dielectric function, refractive index and optical conductivity of the heterostructure are also calculated agreeing with the trends of each other. Desirable band alignment and high absorption coefficient in the visible spectrum can find applications in photovoltaic cells and other opto electronic devices.

单层硒化钨\（（\ text {WSe} _2）\）和碲化镉锌\（（\ text {Cd} _ {0.9} \ text {Zn} _ {0.1} \ text {Te} ）\）异质结构与VDW，即范德华两层之间景点，使用第一原理计算的探讨。从结果中发现，拟议的\（\ text {WSe} _2 / \ text {Cd} _ {0.9} \ text {Zn} _ {0.1} \ text {Te} \}的异质结构几乎是直接的带隙半导体材料，具有交错的（II型）带隙对准，这是光电应用所必需的。此外，结果表明对于单层\（\ text {WSe} _2 \）和\（\ text {Cd} _ {0.9} \ text {Zn} _ {0.1} \ text {Te} \），光吸收在有限的可见光谱（\（\ approx \）  420–470 nm）和（\（\ approx \）  390–430 nm）的有限范围内显着，但是更多的吸收发生在红外（IR ）各个图层的区域。但是，\（\ text {WSe} _2 / \ text {Cd} _ {0.9} \ text {Zn} _ {0.1} \ text {Te} \）异质结构中的吸收导致红移现象和高吸收在整个可见光谱范围内（\（\ approx \） 410–710 nm）。除了吸收光谱外，还计算出异质结构的介电函数，折射率和光导率，这彼此吻合。可见光谱中理想的带取向和高吸收系数可以在光伏电池和其他光电设备中找到应用。