Adsorption and Gas-Sensing Properties of Ag n (n = 1-4) Cluster Doped GeSe for CH 4 and CO Gases in Oil-Immersed Transformer.

The adsorption mechanism of CO and CH 4 on GeSe, modified with the most stable 1-4 Ag-atom clusters, is studied with the help of density functional theory. Adsorption distance, adsorption energy, total density of states (TDOS), projected density of states (PDOS), and molecular orbital theory were all used to analyze the results. CO was found to chemisorb exothermically on GeSe, independent of Ag cluster size, with Ag 4 -GeSe representing the optimum choice for CO gas sensors. CH 4 , in contrast, was found to chemisorb on Ag-GeSe and Ag 2 -GeSe and to physisorb on Ag 3 -GeSe and Ag 4 -GeSe. Here, Ag GeSe was found to be the optimum choice for CH 4 gas sensors. Overall, our calculations suggest that GeSe modified by Ag clusters of different sizes could be used to advantage to detect CO and CH 4 gas in ambient air.