title: In Situ Assembly of Ultrathin PtRh Nanowires to Graphene Nanosheets as Highly Efficient Electrocatalysts for the Oxidation of Ethanol.
abstract: One-dimensional (1D) anisotropic platinum-based nanowires are promising electrocatalysts in polymer electrolyte membrane fuel cells owing to the inherent structural merits. Herein, we report an in situ growth of ultrathin PtRh nanowires (diameters of 2-3 nm) on graphene nanosheets via the oriented attachment pathway. Mechanistic studies reveal that graphene nanosheets play a critical role in the nucleation and growth of PtRh nanowires. The resulting hybrid of PtRh nanowire decorated graphene nanosheets shows outstanding activity and durability toward ethanol electro-oxidation. It exhibits a specific current density of 2.8 mA cm-2and a mass-normalized current density of 1 A mg-1metal, which are 5.4 and 3.1 times those of the state-of-the-art Pt/C catalyst, respectively. After 2000 cyclic tests, it maintains 86% of the initial electrochemically active surface area, which is larger than that of 63% obtained from the Pt/C catalyst. The superior performance is attributed to the combination of the advantageous 1D morphological motif with the synergistic effects of PtRh alloys and graphene nanosheet support.
authors.affiliation: School of Food Science and Engineering, South China University of Technology , Guangzhou 510640, People's Republic of China.
authors.forename: Yi
authors.identifier: http://orcid.org/0000-0003-1923-7588
authors.initials: Y
authors.lastname: Shen
authors.affiliation: School of Food Science and Engineering, South China University of Technology , Guangzhou 510640, People's Republic of China.
authors.forename: Bin
authors.initials: B
authors.lastname: Gong
authors.affiliation: School of Food Science and Engineering, South China University of Technology , Guangzhou 510640, People's Republic of China.
authors.forename: Kaijun
authors.initials: K
authors.lastname: Xiao
authors.affiliation: Shenzhen Key Laboratory of Polymer Science and Technology, College of Materials Science and Engineering, Shenzhen University , Shenzhen 518060, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
keywords: PtRh nanowires; ethanol electro-oxidation; graphene nanosheets; graphene-mediated synthesis; polymer electrolyte membrane fuel cells