Original scientific paper
https://doi.org/10.5599/jese.2012.0020
Platinized titanium dioxide electrodes for methanol oxidation and photo-oxidation
Svetlozar Ivanov
; Rostislaw Kaischew Institute of Physical Chemistry, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria
Ioanna Mintsouli
; Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
Jenia Georgieva
; Rostislaw Kaischew Institute of Physical Chemistry, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria
Stephan Armyanov
; Rostislaw Kaischew Institute of Physical Chemistry, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria
Eugenia Valova
; Rostislaw Kaischew Institute of Physical Chemistry, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria
Georgios Kokkinidis
; Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
Ioannis Poulios
; Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
Sotiris Sotiropoulos
; Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
Abstract
Platinized deposits have been formed on TiO2 particulate films supported on Ti substrates, by means of galvanic replacement of pre-deposited metallic Cu and subsequent immersion of the Cu/TiO2 coatings into a chloroplatinic acid solution. The spontaneous replacement of Cu by Pt results in Pt(Cu)/TiO2/Ti electrodes. Both the platinized and the precursor TiO2/Ti electrodes have been characterized by SEM microscopy/EDS spectroscopy, their surface electrochemistry has been assessed by cyclic voltammetry in the dark and their photoelectrochemical properties by photovoltammetry under UV illumination. It has been found that, although platinized rutile-rich electrodes exhibit typical Pt surface electrochemistry, the anatase-rich electrodes show only traces of oxide formation and stripping. The latter has been translated to a suppression of methanol oxidation at anatase-rich electrodes. On the contrary, methanol oxidation at platinized rutile-rich electrodes occurs at significant rates and can be further enhanced upon UV illumination, as a result of Pt and TiO2 synergism in the photoelectrochemical oxidation of methanol.
Keywords
Titanium dioxide; platinum; galvanic replacement; electrocatalysis; photoelectrocatalysis
Hrčak ID:
91142
URI
Publication date:
10.11.2012.
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