Modeling and Simulation of TiO2/Se Sensor for Detection of CO Gas using COMSOL Multiphysics.: The adsorption simulation on MOS sensor layer exposed to carbon monoxide (CO) gas shows the change in surface concentration.

Abstract

The global gas sensor market was estimated to be worth USD 2.33 billion in 2021. The main areas of application of these sensors are in medical, HVAC systems in industries, air pollution control and house hold safety and security systems. MOS sensors is being used from past three decades, they still suffer from some disadvantages such as high operating temperature, high power consumption, sensor stability and cross sensitivity etc. Since the cost of development of these sensors is high, it is important to develop a mathematical model to economically predict the behaviour of these sensors. In this context, many researches work focused on evaluating the performance of these sensors using numerical analysis software. In this work, Modelling and simulate the gas sensing properties of Titanium dioxide/Selenium (MOS) sensor material to detect carbon monoxide (CO) gas using COMSOL MULTIPHYSICS software. The gas sensing simulation was performed using ‘Reaction engineering’, ‘Transport of diluted species’, ‘Surface reactions’ and ‘Laminar flow’ interfaces of COMSOL MULTIPHYSICS software on Titanium dioxide/Selenium material. Two kinds of simulations, Space independent and space dependent simulation was performed on this material in a constant volume gas chamber. The geometry was created in space dependent node, COMSOL. The carbon monoxide gas was injected through gaussian pulse feed inlet at different concentrations (1 ppm, 5 ppm, 10 ppm and 15 ppm) into the gas chamber and MOS sensor layer was allowed to reach steady state. The adsorption simulation on sensor layer exposed to carbon monoxide (CO) gas shows the change in surface concentration of the adsorbed CO molecules on the sensor layer.