Issue 34, 2015

Two better than one: cobalt–copper bimetallic yolk–shell nanoparticles supported on graphene as excellent cathode catalysts for Li–O2 batteries

Abstract

Despite the extremely high energy density of Li–O2 batteries, the sluggish kinetics severely hinder their practical applications. Here, we report the preparation and electrochemical performance of cost-effective cobalt–copper bimetallic nanoparticles supported on graphene (CoCu/graphene) as the cathode material for Li–O2 batteries. The batteries delivered a high initial discharge capacity of 14 821 mA h g−1 and a low average charge voltage of ∼4.0 V at 200 mA g−1. In addition, the batteries exhibited superior rate capability (7955 mA h g−1 at 800 mA g−1), long cyclability (122 cycles at 200 mA g−1 with a cutoff capacity of 1000 mA h g−1), and outstanding coulombic efficiency (92% at 200 mA g−1). These superior performances resulted from the synergistic effect of non-noble metal Co and Cu supported on graphene, which could simultaneously enhance the oxygen reduction and evolution reaction kinetics. The favorable composite ensures uniform coverage of nanowall-shaped Li2O2 on CoCu/graphene instead of typical toroidal Li2O2 aggregation, thus promoting the reversible formation and decomposition of discharge product Li2O2. The excellent catalytic performance is expected to provide new insights into designing low-cost and high-efficiency cathode materials for Li–O2 batteries and promote their practical applications.

Graphical abstract: Two better than one: cobalt–copper bimetallic yolk–shell nanoparticles supported on graphene as excellent cathode catalysts for Li–O2 batteries

Supplementary files

Article information

Article type
Paper
Submitted
24 Apr 2015
Accepted
20 Jul 2015
First published
20 Jul 2015

J. Mater. Chem. A, 2015,3, 17874-17879

Two better than one: cobalt–copper bimetallic yolk–shell nanoparticles supported on graphene as excellent cathode catalysts for Li–O2 batteries

Y. Chen, Q. Zhang, Z. Zhang, X. Zhou, Y. Zhong, M. Yang, Z. Xie, J. Wei and Z. Zhou, J. Mater. Chem. A, 2015, 3, 17874 DOI: 10.1039/C5TA02990B

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements