Hydrothermal synthesis of MoS2 with tunable band gap for future nano-electronic devices

Abstract

Transition metal dichalcogenides (TMDs) have been explored in various domains of science and technology in the past few years. Among the numerous transition metal dichalcogenides, MoS2 has sparked the interest of researchers owing to its peculiar, layered structure and associated intriguing optical and electrical properties which can be utilized in diverse applications including catalysts, gas sensing, energy storage, hydrogen storage etc. In recent work, the hydrothermal approach is employed to make two distinct morphologies of MoS2, namely Nano-sheets and Nano-flowers, by utilizing ammonium molybdate as a precursor. Herein, X-Ray Diffraction (XRD), Field Emission Scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Fourier Transform Infrared spectroscopy (FTIR), and UV–Visible techniques were utilized to validate the crystallographic structure, morphology, chemical composition, and band gap value of as-synthesized samples. The MoS2 synthesized nanostructures showed a good response for 100 ppm NO2 gas at 100 °C. The synthesized flower-based sensor showed a 24.03 % response and the sheet-based sensor showed a 15.64 % response value for 100 ppm NO2 gas at 100 °C. The versatile morphology of MoS2, coupled with its tunable band gap, open new avenues in the field of gas sensing.