jz5b01417_si_001.pdf (556.29 kB)
Coverage Dependence of Methanol Dissociation on TiO2(110)
journal contribution
posted on 2015-12-17, 09:14 authored by Shuo Liu, An-an Liu, Bo Wen, Ruidan Zhang, Chuanyao Zhou, Li-Min Liu, Zefeng RenAlthough the photochemistry of methanol
on TiO2(110)
has been widely investigated as a prototypical model of the photocatalytic
reaction of organic molecules, the most fundamental question of the
adsorption state of methanol on TiO2(110) is still unclear.
We have investigated the adsorption of methanol on TiO2(110) using sum frequency generation vibrational spectroscopy (SFG-VS)
and density functional theory (DFT) calculations. The SFG results
indicate the dissociation of methanol is highly dependent on the coverage.
The DFT calculations suggest that the methanol prefers the partially
dissociated structure at low coverage, whereas the second layer methanol,
which is hydrogen-bonded to the bridge-bonded oxygen site, largely
blocks the dissociation of the first layer methanol. Our results not
only resolves a long-standing debate regarding the adsorption state
of methanol on TiO2(110) but also provides a detailed insight
into the adsorption structure and sheds light on the photochemistry
on this surface at the molecular level.