Synthesis and NO2 sensing characteristics of Mg-functionalized VO2(M) Nanorods

Abstract

Herein, we report the synthesis, characterization, and potential NO2 gas sensing application of pristine and Mg-doped VO2(M) nanorods sensors. The gas sensing properties of both sensors were tested for various analytes, i.e., CO, CH4, H2S, NO2, SO2 while varying operating temperatures. The sensors demonstrated substantial sensing performance at working temperature of about 120°C, where VO2-Mg outperformed the pristine sensor with a response value of about 59.3%. At ambient temperature (∼25°C), the response values for pristine and VO2-Mg were 3.29% and 6.35%, respectively. The Mg-dopant's catalytic activity alters the electrical characteristics and adsorbed oxygen species on the sensor surface, leading to improved sensing performance. VO2(M)-based sensor‘s sensing mechanism fits the Freundlich isotherm model, thus making the sensors suitable for detecting NO2 at high and ambient temperatures.