NEXAFS studies of the reaction of SO2 with TiO2(100)-(1 × 1) and -(1 × 3)

Adsorption and desorption ofSO2on theTiO2(Sayago1, Serrano2, Böhme3 et al. 2001Phys. Rev. B662220View full textAdd to dashboardCite

“…Moreover, the chemistry of the SO 2 molecule is strongly substrate dependent for oxide surfaces. 7 This is the reason why a strong dispersion of the reported values is observed in Table I. This table has to be understood carefully, because one should be aware of the difficulties in giving absolute binding energies of atoms in molecules deposited on oxide surfaces.…”

“…Since it is very difficult to have a realistic spectroscopic quantification of the number of vacancies, we cannot correlate the amount and nature of the species to the surface defects. 7,14 A previous work on the adsorption of SO 2 on TiO 2 ͑110͒ has shown that there is molecular adsorption for temperatures below 105 K. 5 From this temperature the authors noticed that the adsorbed SO 2 transforms with temperature in sulphite and sulphatelike phases. Our study has been carried out at temperatures around 120 K, i.e., above 105 K, a temperature where the reaction process could be already started.…”

“…In this direction, Raza et al 7 have shown that there is a similarity in the adsorption behavior of SO 2 on two different TiO 2 surfaces, suggesting that the chemical bonding dominates the process. Accordingly, we have shown that the impinging SO 2 molecules react strongly with the surface oxygen atoms from the substrate to form more oxidized species.…”

“…[3][4][5][6][7] These previous works lead to different results. For room-temperature adsorption ͑RT͒ either little reaction 3 or the formation of surface sulphite (SO 5 2Ϫ ) 4 has been reported.…”

A Review of Quantitative Structural Determinations of Adsorbates on Metal Oxide Surfaces

“…90 Surfaces were prepared by Ar + sputtering and annealing, with either a final anneal in 1 × 10 −6 mbar of O 2 , or a 10 min anneal in vacuum at 1100 K to produce the (1 × 1) and (1 × 3) surfaces, respectively. SO 2 exposure was carried out at 110 K to achieve ∼ 0.5 ML coverage (where 1 ML is defined as occupation of all of the O and Ti surface atom sites by sulphur-containing species).…”