Exploring the sensing ability of <scp>B</scp>‐ and <scp>Si</scp>‐doped <scp>WS<sub>2</sub></scp> monolayer toward <scp>CO</scp> and <scp>NO</scp> gas
Duy Khanh Nguyen, Duc‐Quang Hoang, D.M. Hoat
Abstract
Abstract Searching for new two‐dimensional (2D) materials to capture toxic gas molecules has drawn great attention from scientific community. In this work, the adsorption of CO and NO molecules on B‐ and Si‐doped WS 2 monolayer (B:WS 2 and Si:WS 2 ) has been explored using first‐principles calculations. Pristine WS 2 monolayer is a non‐magnetic semiconductor with an energy gap of 1.81 eV. It is magnetized upon doping with B atom to form a half‐metallic material, meanwhile the paramagnetic nature is preserved upon Si doping. CO and NO molecules are weakly physisorbed on pristine WS 2 monolayer. Doping strategies enhance significantly the adsorption process decreasing drastically the adsorption energy. The adsorbed gas molecules alter considerably the fundamental properties of the doped systems. Specifically, the magnetic properties of B:WS 2 system are quenched by both CO and NO molecules to form paramagnetic metallic and semiconductor materials, respectively. CO adsorption increases the energy gap of Si:WS 2 system, meanwhile the adsorbed NO molecule induces significant magnetism, leading to the emergence of the half‐metallicity. Results presented herein may recommend B‐ and Si‐doped WS 2 monolayer as promising candidates to detect and capture CO and NO molecules. Moreover, doping strategy may be used to functionalize 2D transition metal dichalcogenides for toxic gas sensing.