Enhanced Sensitivity of CO on Two-Dimensional, Strained, and Defective GaSe

Molecules

Huei-Ru Fuh¹  Ching-Ray Chang²  Hsin-Pan Huang³ 

[1] Department of Chemical Engineering and Materials Science, Yuan Ze University, Taoyuan 32003, Taiwan;Department of Physics, National Taiwan University, Taipei 10617, Taiwan;Graduate Institute of Applied Physics, National Taiwan University, Taipei 10617, Taiwan;

关键词: two-dimensional material;    CO sensing;    vacancy;    strain effect;    first-principles study;   

DOI  :  10.3390/molecules26040812

来源: DOAJ

【 摘 要 】

The toxic gas carbon monoxide (CO) is fatal to human beings and it is hard to detect because of its colorless and odorless properties. Fortunately, the high surface-to-volume ratio of the gas makes two-dimensional (2D) materials good candidates for gas sensing. This article investigates CO sensing efficiency with a two-dimensional monolayer of gallium selenide (GaSe) via the vacancy defect and strain effect. According to the computational results, defective GaSe structures with a Se vacancy have a better performance in CO sensing than pristine ones. Moreover, the adsorption energy gradually increases with the scale of tensile strain in defective structures. The largest adsorption energy reached −1.5 eV and the largest charger transfer was about −0.77 e. Additionally, the CO gas molecule was deeply dragged into the GaSe surface. We conclude that the vacancy defect and strain effect transfer GaSe to a relatively unstable state and, therefore, enhance CO sensitivity. The adsorption rate can be controlled by adjusting the strain scale. This significant discovery makes the monolayer form of GaSe a promising candidate in CO sensing. Furthermore, it reveals the possibility of the application of CO adsorption, transportation, and releasement.

【 授权许可】

Unknown