Synthesis and Characterization of Pt-Ag Icosahedral Nanocages with Enhanced Catalytic Activity toward Oxygen Reduction

Wenxia Wang, Yifeng Shi, Zitao Chen, Ming Zhao, Zhenming Cao, Zhiheng Lyu, Ruhui Chen, Kaijun Xiao, Miaofang Chi, Younan Xia

Research output: Contribution to journalArticlepeer-review

2 Scopus citations

Abstract

There is an urgent need to develop cost-effective electrocatalysts based on Pt for a broad spectrum of applications, including those vital to the operation of fuel cells. Hollowing out the interior of Pt nanocrystals offers a simple and viable strategy for maximizing the utilization efficiency of this precious metal while enhancing the electrocatalytic performance. Herein, we report the synthesis and electrocatalytic evaluation of Pt−Ag icosahedral nanocages with an average wall thickness of 1.6 nm. The Pt atoms are coated on the surface of Ag icosahedral seeds, leading to the formation of Ag@PtnL core-shell icosahedral nanocrystals with tunable shell thicknesses. The core-shell nanocrystals are then converted to icosahedral nanocages by selectively etching away the Ag in the core. The as-obtained nanocages with a composition of Pt4.5Ag exhibit an almost 3-fold enhancement in specific activity toward oxygen reduction relative to the commercial Pt/C in acid media.

Original languageEnglish
Article numbere202200186
JournalChemNanoMat
Volume8
Issue number9
DOIs
StatePublished - Sep 2022

Funding

This work was supported in part by a grant from the NSF (CHE-2105602) and startup funds from the Georgia Institute of Technology. As a visiting Ph.D. student from South China University of Technology, W.W. was also partially supported by the Oversea Study Program of Guangzhou Elite Project. The TEM, STEM, and XRD analyses were carried at the Georgia Tech Institute for Electronics and Nanotechnology, a member of the National Nanotechnology Coordinated Infrastructure (NNCI), which is supported by the National Science Foundation (ECCS-2025462). Part of the characterization was supported by an Early Career project supported by DOE Office of Science FWP #ERKCZ55-KC040304 and was performed at Oak Ridge National Laboratory's (ORNL) Center for Nanophase Materials Sciences (CNMS), which is a DOE Office of Science User Facility.

FundersFunder number
Center for Nanophase Materials Sciences
Oversea Study Program of Guangzhou Elite Project
National Science FoundationECCS-2025462, CHE-2105602
Office of Science55-KC040304
Oak Ridge National Laboratory
Georgia Institute of Technology
South China University of Technology

    Keywords

    • catalysis
    • hollow nanocrystals
    • icosahedra
    • oxygen reduction reaction

    Fingerprint

    Dive into the research topics of 'Synthesis and Characterization of Pt-Ag Icosahedral Nanocages with Enhanced Catalytic Activity toward Oxygen Reduction'. Together they form a unique fingerprint.

    Cite this