Enhanced oxygen reduction activity of size-selected platinum subnanocluster catalysts: Ptn (n = 3–9)

• Published in: Catalysis science & technology 2022-01, Vol.12 (5), p.1400-1407
• Main Authors: Ohnuma, Akira, Takahashi, Koki, Tsunoyama, Hironori, Inoue, Tomoya, Zhao, Pei, Velloth, Archana, Ehara, Masahiro, Ichikuni, Nobuyuki, Tabuchi, Masao, Nakajima, Atsushi
• Format: Article
• Language: eng ; jpn
• Subjects: Catalysts; Catalytic activity; Crystallites; Density functional theory; Fine structure; Fuel cells; Glassy carbon; Nanoclusters; Nuclear fuels; Platinum; Reaction intermediates; Substrates; X ray absorption
• ISSN: 2044-4753; 2044-4761
• DOI: 10.1039/d1cy00573a

Nanoclusters (NCs) are promising candidates to improve catalytic activity despite the controversial size specificity, because atomicity is a crucial parameter that determines the activity of platinum (Pt) NCs. This paper demonstrates the enhanced catalytic activity based on the charge redistribution in Pt sub-NCs containing three to nine Pt atoms (Ptn; n = 3–9) on a glassy carbon substrate. The sub-NCs show 1.6–2.2 times higher activity than the standard Pt/C catalysts with a Pt crystallite diameter of 2 nm. The geometric structures are identified using rigorous structure analyses by X-ray absorption fine structure spectroscopy and density functional theory, and the activity origin within the supported Pt sub-NCs is theoretically discussed from viewpoints of energetics for reaction intermediates in the electrochemical processes. It should be possible to use sub-NCs in future fuel cell technologies as an active catalyst with a high atomic efficiency.