The Interaction of CO Gas Molecules with TiO2/WSe2 Nanocomposites: Towards Superior Gas Sensors

The mechanism of CO sensing on N-doped TiO2/WSe2 nanocomposites was explained bydensity functional theory calculations. The results indicate that the TiO2 side of TiO2/WSe2nanocomposite is the most stable interaction site, and its fivefold coordinated titanium sites werefound to be the most favorable binding sites. The carbon atom of CO molecule movespreferentially towards the titanium atoms. A single contacting point was formed between thenanocomposite and adsorbed molecule. The interaction of CO molecule with N-dopedTiO2/WSe2 nanocomposite is found to be more favorable in energy than that with pristinenanocomposite [1]. This supports the notion that the N-doped nanocomposites are highly sensitiveto CO detection. Thus, nitrogen doping has activating effect on the adsorption of CO byTiO2/WSe2 based adsorbents. Mulliken population analysis was also conducted in order todescribe the charge transfer between the nanocomposite and adsorbed molecule. The resultssuggest that the charge was transferred from the nanocomposite to the molecule, implying thatCO acts as charge acceptor. The significant overlaps between the PDOSs of the interacting atomsshow the formation of chemical bonds between them [2]. The results propose a great potential ofTiO2/WSe2 nanocomposites for application as a highly efficient molecule sensors.

کلیدواژه ها:

Adsorption ، Density Functional Theory ، DOS ، CO ، TiO2/WSe2 Nanocomposite