Surface Morphology Evolution of MoS2–x by Growth Temperature and Its Effect on Photodetector Properties

MoS2, being an attractive two-dimensional (2-D) material, has gradually become a research hotspot in recent years. Herein, the MoS2–x thin films are grown through a chemical vapor deposition technique by varying the sulfurization temperature from 700 to 900 °C. X-ray diffraction profile reveals the highly crystalline nature of the sample grown at 800 °C and results in the improved directional orientation of the atoms. A decrement in the intensity of the S 2p peak for the thin film sulfurized at 800 °C signifies the diffusion of the sulfur atoms into the molybdenum atoms, prominently resulting in the development of a nanostructured morphology. The formation of an ohmic contact between the photoactive material and the electrode results in the fast transportation of the charge carriers through the metal-semiconductor interface. The sample grown at 800 °C, achieves a high photocurrent, a sharp rise time, and a superior responsivity of 112.49 μA, 35 ms, and 2.69 A/W, respectively, under the illumination of the visible light (λ = 550 nm) and optical power density of 0.1667 mW/cm2 attributed to its higher crystalline nature and formation of prominent nanoflake-structured morphology. Finally, with superior figures of merit, the fabricated photodetector signifies its potential for application in optoelectronics devices.