Adsorption and sensing performances of Rh-embedded PtSe2 monolayer upon CO and HCHO in dry-type reactors: A first-principles study

Based on the first-principles method, we theoretically analyze the Rh-embedded PtSe2 (Rh-PtSe2) monolayer as a potential gas sensor in this paper, for detection of CO and HCHO in the dry-type reactor to evaluate its operation status. The Rh-embedding behavior is performed by substituting a Se atom at the topmost Se layer of the pristine PtSe2 monolayer, and we find that the Rh atom can be stably and energy-favorably embedded in the PtSe2 monolayer with the formation energy (E-form) of -0.53 eV. Chemisorption is identified for the CO and HCHO system, with the adsorption energy (E-ad) as -1.89 and -1.05 eV, respectively. The electronic property analysis reveals that the Rh-PtSe2 monolayer can be a promising resistance-type sensor or a field-effect transistor sensor for detection of two gas species, with good sensing response or selectivity. This theoretical work can pave the way to further investigate the sensing application of Rh-PtSe2 monolayer upon toxic gases in the dry-type reactors, and related experimental research can verify our findings and to confirm that Rh-PtSe2 monolayer is a promising sensing candidate to evaluate the operation status of the dry-type reactors in the power system.