Open AccessWater‐mediated photo‐induced reduction of platinum films
Author(s) -
Fraxedas Jordi,
Zhang Kuan,
Sepúlveda Borja,
Esplandiu María José,
García de Andrés Xènia,
Llorca Jordi,
Pérez-Dieste Virginia,
Escudero Carlos
Publication year - 2019
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s1600577519004685
Subject(s) - platinum , desorption , adsorption , x ray photoelectron spectroscopy , metal , photochemistry , chemistry , materials science , oxygen , inorganic chemistry , analytical chemistry (journal) , catalysis , chemical engineering , metallurgy , organic chemistry , engineering
Platinum thin films activated ex situ by oxygen plasma become reduced by the combined effect of an intense soft X‐ray photon beam and condensed water. The evolution of the electronic structure of the surface has been characterized by near‐ambient‐pressure photoemission and mimics the inverse two‐step sequence observed in the electro‐oxidation of platinum, i.e. the surface‐oxidized platinum species are reduced first and then the adsorbed species desorb in a second step leading to a surface dominated by metallic platinum. The comparison with measurements performed under high‐vacuum conditions suggests that the reduction process is mainly induced by the reactive species generated by the radiolysis of water. When the photon flux is decreased, then the reduction process becomes slower.