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Small Reduced Graphene Oxides for Highly Efficient Oxygen Reduction Catalysts.

ABSTRACT: We demonstrated highly efficient oxygen reduction catalysts composed of uniform Pt nanoparticles on small, reduced graphene oxides (srGO). The reduced graphene oxide (rGO) size was controlled by applying ultrasonication, and the resultant srGO enabled the morphological control of the Pt nanoparticles. The prepared catalysts provided efficient surface reactions and exhibited large surface areas and high metal dispersions. The resulting Pt/srGO samples exhibited excellent oxygen reduction performance and high stability over 1000 cycles of accelerated durability tests, especially the sample treated with 2 h of sonication. Detailed investigations of the structural and electrochemical properties of the resulting catalysts suggested that both the chemical functionality and electrical conductivity of these samples greatly influence their enhanced oxygen reduction efficiency.

SUBMITTER: Bak SJ

PROVIDER: S-EPMC8625579 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Small Reduced Graphene Oxides for Highly Efficient Oxygen Reduction Catalysts.

Bak Su-Jeong SJ Kim Sun-I SI Lim Su-Yeong SY Kim Taehyo T Kwon Se-Hun SH Lee Duck Hyun DH

International journal of molecular sciences 20211114 22

We demonstrated highly efficient oxygen reduction catalysts composed of uniform Pt nanoparticles on small, reduced graphene oxides (srGO). The reduced graphene oxide (rGO) size was controlled by applying ultrasonication, and the resultant srGO enabled the morphological control of the Pt nanoparticles. The prepared catalysts provided efficient surface reactions and exhibited large surface areas and high metal dispersions. The resulting Pt/srGO samples exhibited excellent oxygen reduction performa ...[more]

PMID: 34830182

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