Iridium oxide supported on conductive doped tin oxides shows many attractive properties such as: high water-splitting activity and significantly high durability in acidic media [1]. Especially, Iridium oxide synthesized from Iridium alloy with non-noble metal can’t only reduce the loading of Iridium but also create a favorable conditions for the formation of core-shell structure [2]. Supporting for Iridium oxide, doped tin oxide plays the key role on the stability and activities of catalyst system. While pure FTO films showed the highest stability in acidic media, ITO have highest conductivity and Iridium oxide had the highest activity on meso-ATO powder in the comparison between ATO, FTO and ITO [3, 4]. However, the metal support interaction (MSI) during the formation of Iridium based alloys as well as their oxidation to form the core-shell structure, was still a largely remained unaddressed issue [5, 6]. On this report, the Iridium-oxide-based alloys synthesized by polyol method, supported on doped tin oxide powder with variety particle sizes. Both of the initial support’s and the supported catalysts’ surfaces were characterized by ICP, BET, SEM, XRD, XPS and RDE. Therefore, the affections of surface area, particle size, conductivity and doping content of the supports, onto the catalyst’s structure, activity and stability was also investigated. Low surface area (27 m2/gr) and high particle size support lowed down the MSI resulted in the agglomerate of IrM alloys and limited the formation of core-shell structure and activity of catalyst. The highest mesoporous doped tin oxide synthesized (240m2 /gr) showed their most promising support for the uniform distribution, high durability, and activity of Iridium oxide catalyst.

1. Nong, H.N., et al., IrOx core-shell nanocatalysts for cost- and energy-efficient
electrochemical water splitting. Chem. Sci., 2014. 5(8): p. 2955-2963.
2. Nong, H.N., Synthese und Charakterisierung von Kern-Schale-Metalloxid-
Nanopartikel für effiziente elektrochemische Wasserspaltung. 2015,
Technische Universität Berlin.
3. Oh, H.-S., H.N. Nong, and P. Strasser, Preparation of Mesoporous Sb-, F-,
and In-Doped SnO2Bulk Powder with High Surface Area for Use as Catalyst
Supports in Electrolytic Cells. Advanced Functional Materials, 2015. 25(7): p.
1074-1081.
4. Geiger, S., et al., Stability limits of tin-based electrocatalyst supports.
Scientific Reports, 2017. 7(1): p. 4595.
5. Ma, Q., et al., Interaction between Catalyst and Support. 2. Low Coverage of
Co and Ni at the Alumina Surface. The Journal of Physical Chemistry B, 2001.
105(11): p. 2212-2221.
6. Campbell, C.T., Electronic perturbations. Nature Chemistry, 2012. 4: p. 597.