Exploring the photoelectric properties of 2D MoS 2 thin films grown by CVD

Two-dimensional MoS 2 with a layered structure has excellent optoelectronic properties in theory, but MoS 2 films prepared by chemical vapor deposition (CVD) method are still underexplored in optoelectronic applications. Hence, different layers of MoS 2 films were prepared on sapphire substrate by CVD in this article. After structural characterization, the optoelectronic properties of MoS 2 films with different number of layers under specific wavelength laser irradiation (365 nm, 532 nm, 650 nm) were explored, and the improvement of properties after annealing. The experimental results manifested that the multilayer MoS 2 film had the highest sensitivity (0.589 mA/W), and the monolayer MoS 2 film had the highest on/off ratio (34.68) to violet light. Furthermore, the annealed monolayer MoS 2 had the shortest response and recovery time of only 3 s. The results demonstrated the great potential of two-dimensional MoS 2 films in the field of photodetection and contributed to the development of a new generation of optoelectronic devices. Graphical abstract