The Role of TiO2 Doping on RuO2-Coated Electrodes for the Water Oxidation ReactionShow others and affiliations
2013 (English)In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 117, no 12, p. 6126-6135Article in journal (Refereed) Published
Abstract [en]
Electrochemical water splitting into H2 and O2 presents a significant and challenging energy loss due to the high overpotential required at the anode. Today, in industrially relevant applications, dimensionally stable anodes (DSA) based on the electrocatalytic active RuO2 are conventionally utilized. To enhance the resistance against corrosion, incorporation of TiO2 in the RuO2-coated electrodes is widely employed. In the present work we have used scanning electrochemical microscopy (SECM) to demonstrate that TiO2-doped RuO2-coated electrodes, in addition to being more durable, also show an electrocatalytic activity that is, on average, 13% higher as compared to the pure RuO2-coated electrodes. We also demonstrate that cracks in the pure RuO2 coating are the most active zones, probably because Ti from the Ti support has diffused into the first applied layer of the RuO2 coating. To reveal the nature of this enhanced activity for water oxidation displayed on TiO2-doped RuO2 electrodes, we have employed X-ray photoelectron spectroscopy (XPS) for material characterization. The results show that the electrocatalytic activity enhancement displayed on the mixed (Ru1−x:Tix)O2 coating is promoted through a charge transfer from the RuO2 to the TiO2, which provides new and more reactive sites designated as activated RuO2δ+.
Place, publisher, year, edition, pages
2013. Vol. 117, no 12, p. 6126-6135
National Category
Physical Chemistry
Identifiers
URN: urn:nbn:se:miun:diva-18571DOI: 10.1021/jp308941gScopus ID: 2-s2.0-84875750061OAI: oai:DiVA.org:miun-18571DiVA, id: diva2:610192
Note
Publication Date (Web): February 11, 2013
2013-03-082013-03-082017-12-06Bibliographically approved