Impact of sp2 carbon material species on Pt nanoparticle-based electrocatalysts produced by one-pot pyrolysis methods with ionic liquids

Yu Yao; Qingning Xiao; Masafumi Kawaguchi; Tetsuya Tsuda; Hirohisa Yamada; Susumu Kuwabata

doi:10.1039/d2ra01330d

Impact of sp² carbon material species on Pt nanoparticle-based electrocatalysts produced by one-pot pyrolysis methods with ionic liquids

RSC Adv. 2022 May 11;12(22):14268-14277. doi: 10.1039/d2ra01330d. eCollection 2022 May 5.

Authors

Yu Yao^{1

2}, Qingning Xiao¹, Masafumi Kawaguchi¹, Tetsuya Tsuda^{1

3}, Hirohisa Yamada², Susumu Kuwabata^{1

4}

Affiliations

¹ Department of Applied Chemistry, Graduate School of Engineering, Osaka University 2-1 Yamada-oka, Suita Osaka 565-0871 Japan ttsuda@chiba-u.jp kuwabata@chem.eng.osaka-u.ac.jp.
² Department of Chemical Engineering, National Institute of Technology, Nara College 22 Yata-cho, Yamatokoriyama Nara 639-1080 Japan.
³ Department of Materials Science, Graduate School of Science and Engineering, Chiba University 1-33 Yayoicho, Inage-ku Chiba 263-8522 Japan.
⁴ Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University 2-1 Yamada-oka, Suita Osaka 565-0871 Japan.

Abstract

Pt-nanoparticle-supported graphene nanoplatelets (Pt/GNPs) and multiwalled carbon nanotube composite (Pt/MWCNTs) electrocatalysts for the oxygen reduction reaction (ORR) can be prepared using a one-pot method through the pyrolytic decomposition of the platinum precursor, platinum(ii) bis(acetylacetonate) (Pt(acac)₂) in 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ([C₄mim][Tf₂N]) or N,N,N-trimethyl-N-propylammonium bis(trifluoromethanesulfonyl)amide ([N_1,1,1,3][Tf₂N]) ionic liquids (ILs) with the target sp² carbon support. In this one-pot pyrolysis method, which does not require any reagents to reduce Pt metal precursors or stabilize Pt nanoparticles, Pt nanoparticles are readily immobilized onto the sp² surface by a thin IL layer formed at the interface, which can work as a binder. We used three types of sp² carbon materials with different geometric shapes (graphene nanoplatelets with <3 (GNPs-3) and 18-24 layers (GNPs-20) and multiwalled carbon nanotubes (MWCNTs)) to investigate Pt nanoparticle formation and anchoring. All the electrocatalysts, especially Pt/MWCNTs, showed higher durability than the commercial catalyst owing to the combined effect of the IL binder and sp² carbon materials. Our findings strongly suggest that the original carbon surface properties are also an important factor for creating high-performance ORR electrocatalysts.