Electronic and optical properties of Zr2CO2/WS2 van der Waals heterostructures: First-principles study

Enhancing the photosensitivity and response speed of transition metal dichalcogenides (TMDs)-based photodetectors through the construction of semiconductor heterostructures poses an ongoing challenge in optoelectronic devices field. In this study, we conducted a systematic investigation using first-principles calculations to explore the characteristics of MXene/TMDs heterostructures, specifically focusing on the Zr2CO2/WS2 heterostructure. Computational analysis verifies that the Zr2CO2/WS2 heterostructure displays a type II band alignment, which facilitates efficient carrier separate transportation within the heterostructure. In both the zigzag and armchair directions, the heterostructure formation enhances the carrier mobilities. Furthermore, modulation of the heterostructure is accomplished by applying external electric fields and axial stress. Notably, the light absorption ability of the Zr2CO2/WS2 heterostructure is more sensitive to external electric fields rather than interlayer distance. Overall, Zr2CO2/WS2 van der Waals heterostructures offer inherent advantages for the development of high-performance photodetectors.