Metal and Metal Oxide Interactions and Their Catalytic Consequences for Oxygen Reduction Reaction

Journal Article · Thu Jun 01 04:00:00 EDT 2017 · Journal of the American Chemical Society

DOI:https://doi.org/10.1021/jacs.7b02378· OSTI ID:1409565

Jia, Qingying; Ghoshal, Shraboni; Li, Jingkun; Liang, Wentao; Meng, Guangnan ^[1]; Che, Haiying ^[2]; Zhang, Shiming ^[2]; Ma, Zi-Feng ^[2]; Mukerjee, Sanjeev

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1. ULVAC Technologies, Inc., 401 Griffin Brook Drive, Methuen, Massachusetts 01844, United States
2. Shanghai Electrochemical Energy Devices Research Center, Department of Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, People’s Republic of China

Many industrial catalysts are composed of metal particles supported on metal oxides (MMO). It is known that the catalytic activity of MMO materials is governed by metal and metal oxide interactions (MMOI), but how to optimize MMO systems via manipulation of MMOI remains unclear, due primarily to the ambiguous nature of MMOI. Herein, we develop a Pt/NbOx/C system with tunable structural and electronic properties via a modified arc plasma deposition method. We unravel the nature of MMOI by characterizing this system under reactive conditions utilizing combined electrochemical, microscopy, and in situ spectroscopy. We show that Pt interacts with the Nb in unsaturated NbOx owing to the oxygen deficiency in the MMO interface, whereas Pt interacts with the O in nearly saturated NbOx, and further interacts with Nb when the oxygen atoms penetrate into the Pt cluster at elevated potentials. While the Pt–Nb interactions do not benefit the inherent activity of Pt toward oxygen reduction reaction (ORR), the Pt–O interactions improve the ORR activity by shortening the Pt–Pt bond distance. Pt donates electrons to NbOx in both Pt–Nb and Pt–O cases. The resultant electron efficiency stabilizes low-coordinated Pt sites, hereby stabilizing small Pt particles. This determines the two characteristic features of MMO systems: dispersion of small metal particles and high catalytic durability. These findings contribute to our understandings of MMO catalytic systems.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• DOE Contract Number: SC0012704
• OSTI ID: 1409565
• Report Number(s): BNL--114617-2017-JA¿¿¿
• Journal Information: Journal of the American Chemical Society, Journal Name: Journal of the American Chemical Society Journal Issue: 23 Vol. 139; ISSN 0002-7863
• Publisher: American Chemical Society (ACS)
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY