Stoichiometry modulated tunable optoelectronic properties of Nb-doped WS2 synthesized by chemical vapor deposition method

Significant progress has been made in the field of two-dimensional WS 2 , yet the precise control of the doping process to achieve desired properties and the interpretation of complex physical phenomena in these novel materials necessitate thorough research. In this study, Nb-doped WS 2 is synthesized using chemical vapor deposition technology, leading to triangular flakes with a side length of 12–20 μm. The X-ray photoelectron spectroscopy analysis indicates that the Nb W substitution defect functions as an electron acceptor. The interlayer and transverse forces of the Nb-doped WS 2 flake approach 1 nN and 150 pN, respectively. As the doping concentration increases, the valence band maximum energy of Nb-doped WS 2 ranges from 4.06 eV to 4.3 eV. Furthermore, the performance of the photodetector is discussed.