Issue 1, 2020

Exceptional performance of hierarchical Ni–Fe oxyhydroxide@NiFe alloy nanowire array electrocatalysts for large current density water splitting

Abstract

Water electrolysis represents a promising sustainable hydrogen production technology. However, in practical application which requires extremely large current densities (>500 mA cm−2), the oxygen evolution reaction (OER) becomes unstable and kinetically sluggish, which is a major hurdle to large-scale hydrogen production. Herein, we report an exceptionally active and binder-free NiFe nanowire array based OER electrode that allows durable water splitting at current densities up to 1000 mA cm−2 up to 120 hours. Specifically, NiFe oxyhydroxide (shell)–anchored NiFe alloy nanowire (core) arrays are prepared via a magnetic-field-assisted chemical deposition method. The ultrathin (1–5 nm) and amorphous NiFe oxyhydroxide is in situ formed on the NiFe alloy nanowire surface, which is identified as an intrinsically highly active phase for the OER. Additionally, the fine geometry of the hierarchical electrode can substantially improve charge and mass (reactants and oxygen bubbles) transfer. In an alkaline electrolyte, this OER electrode can yield current densities of 500 and 1000 mA cm−2 stably over 120 hours at overpotentials of only 248 mV and 258 mV respectively, which are dramatically lower than any recently reported overpotentials. Notably, the integrated alkaline electrolyzer (with pure Ni nanowires as HER electrode) is demonstrated to reach the current density of 1000 mA cm−2 with super low voltage of 1.76 V, outperforming the state-of-the-art industrial catalysts. Our result may represent a critical step towards an industrial electrolyzer for large-scale hydrogen production by water splitting.

Graphical abstract: Exceptional performance of hierarchical Ni–Fe oxyhydroxide@NiFe alloy nanowire array electrocatalysts for large current density water splitting

Supplementary files

Article information

Article type
Communication
Submitted
26 Jul 2019
Accepted
04 Okt 2019
First published
08 Okt 2019

Energy Environ. Sci., 2020,13, 86-95

Exceptional performance of hierarchical Ni–Fe oxyhydroxide@NiFe alloy nanowire array electrocatalysts for large current density water splitting

C. Liang, P. Zou, A. Nairan, Y. Zhang, J. Liu, K. Liu, S. Hu, F. Kang, H. J. Fan and C. Yang, Energy Environ. Sci., 2020, 13, 86 DOI: 10.1039/C9EE02388G

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