Reactivity and reaction intermediates for acetic acid adsorbed on CeO2(111)

CALAZA, FLORENCIA C.; CHEN, TSUNG-LIANG; MULLINS, DAVID R.; XU, YE; OVERBURY, STEVEN H.

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ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2015 vol. 253 p. 65 - 76

0920-5861

Adsorption and reaction of acetic acid on a CeO2(1 1 1) surface was Studied by a combination of ultra-high vacuum based methods including temperature desorption spectroscopy (TPD), soft X-ray photoelectronspectroscopy (sXPS), near edge X-ray absorption spectroscopy (NEXAFS) and reflection absorption IR spectroscopy (RAIRS), together with density functional theory (DFT) calculations. TPD shows that the desorption products are strongly dependent upon the initial oxidation state ofthe CeO2 surface, including selectivity between acetone and acetaldehyde products. The combination of sXPS and NEXAFS demonstrate that acetate forms upon adsorption at low temperature and is stable to above 500K, above which point ketene, acetone and acetic acid desorb. DFT and RAIRS show that below 500K, bridge bonded acetate coexists with a moiety formed by adsorption of an acetate at an oxygen vacancy, formed by water desorption.