Enhanced electrocatalytic performance for hydrogen oxidation reaction on gold nanoparticles supported on tungsten oxide (VI) modified carbon Ji-Hoon Jang a , Eunjik Lee b , Young-Uk Kwon a,b,c, * a Center for Human Interface Nano Technology, Sungkyunkwan University, Suwon 440-746, Republic of Korea b SKKU Advanced Institute of Nanotechnology, Sungkyunkwan University, Suwon 440-746, Republic of Korea c Department of Chemistry, BK21 School of Chemical Materials Science, Sungkyunkwan University, Suwon 440-746, Republic of Korea article info Article history: Received 24 October 2011 Received in revised form 2 March 2012 Accepted 4 March 2012 Available online 24 March 2012 Keywords: Gold Tungsten oxide Electrocatalysts Sonochemistry Hydrogen oxidation abstract We report on a hydrogen oxidation reaction (HOR) catalyst system composed of gold nanoparticles (Au NPs) and tungsten oxide (WO 3 ). Previously, we reported that Au NPs could be activated for HOR by sonochemical heating and quenching. However, we also found that the activated Au NPs were poisoned by protons, the HOR product. In order to further improve the catalytic behavior of Au NPs, we employed tungsten oxide as a part of the support and a co-catalyst, by which proton spillover could be achieved. Au NPs sup- ported on WO 3 /C were synthesized. The intermediates and final product were character- ized by powder X-ray diffraction, energy dispersive X-ray spectroscopy, and transmission electron microscopy. Electrocatalytic activity of the samples for HOR was investigated by the linear sweep voltammetry with rotating disk electrode technique, which showed the disappearance of the proton poisoning of Au NPs in contact with WO 3 . Therefore, with sonication treatment, the Au NPs and WO 3 composite showed a very high and stable activity for HOR. Copyright ª 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. 1. Introduction Electrochemical hydrogen oxidation reaction (HOR) has attracted extensive attention for its importance in polymer electrolyte membrane fuel cells (PEMFCs). Durable and economical catalysts are a key requirement for the future development of PEMFCs. However, to date, catalysts with a certain level of HOR activity have been limited to Pt and Pt- containing materials; the high cost and the limited resources of Pt are one of the major hurdles [1e7]. In addition, the CO poisoning of Pt is a serious practical problem because most of the large scale production processes of hydrogen are bound to have CO contamination. Naturally, attempts to discover HOR catalysts with no or a little of Pt have been made. Promising results have been reported from studies on multimetallic alloy systems [8e21] and multifunctional electrocatalysts [22,23]. However, their performance is still considerably poorer than that of Pt. In this regard, our group has previously demonstrated that pure gold nanoparticles (Au NPs) can become HOR-active through an ultrasound treatment [24]. The activity of such Au NPs was comparable to that of Pt. The origin of the catalytic * Corresponding author. Department of Chemistry, BK21 School of Chemical Materials Science, 300 Chunchun Dong, Jang-An Gu, Suwon 440-746, Republic of Korea. Tel.: þ82 31 290 7070; fax: þ82 31 290 7075. E-mail address: ywkwon@skku.edu (Y.-U. Kwon). Available online at www.sciencedirect.com journal homepage: www.elsevier.com/locate/he international journal of hydrogen energy 37 (2012) 8170 e8176 0360-3199/$ e see front matter Copyright ª 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ijhydene.2012.03.012