Single-step CVD synthesis of layered WS2 films for NO2 gas sensing

Recently layered inorganic materials analogues to graphene such as two-dimensional transition metal dichalcogenides (2D TMDs) have emerged as promising building blocks for the gas sensing industry. Indeed, they show impressive semiconducting properties, tunable band gap, large surface area and excellent gas adsorbing capacities. Herein, we report for the first time, on a single step synthesis of 3D assembly of layered WS2 sensing material, via hydrogen free, atmospheric pressure CVD technique, directly on silicon oxide substrate for NO2 resistive gas sensing application. E-SEM, EDX and Raman spectroscopy were used to investigate the morphology and composition of the grown material. Demonstration of WS2 sensor towards one of the most pollutant gases (NO2) showed promising results with high sensitivity and low detection limit below 20 ppb.