|
Abstract
|
The adsorption of hydrogen sulfide molecule on undoped and N-doped
TiO 2 /Au nanocomposites was investigated by density functional theory
(DFT) calculations. The results showed that the adsorption energies of H 2 S
on the nanocomposites follow the order of 2N doped (Ti site)>N-doped (Ti
site)>Undoped (Ti site). The structural properties including bond lengths,
angles and adsorption energies and electronic properties in view of the
projected density of states (PDOSs) and molecular orbitals (MOs) were
analyzed in detail. The results indicated that the interaction between H 2 S
molecule and N-doped TiO 2 /Au nanocomposite is stronger than that be-
tween H 2 S and undoped nanocomposite, suggesting that N-doping helps
to strengthen the interaction of H 2 S with TiO 2 /Au nanocomposite. Mul-
liken population analysis was conducted to analyze the charge transfer
between the nanocomposite and H 2 S molecule. Although H 2 S molecule
has no significant interaction with undoped nanocomposite, it tends to
be strongly adsorbed on the N-doped nanocomposite. The results also
suggest that the two doped nitrogen atoms in TiO 2 greatly strengthen the
adsorption process, being a helpful procedure to help in the design and
development of improved sensor devices for H 2 S detection
|