Cactus-Like Hollow Cu2-x S@Ru Nanoplates as Excellent and Robust Electrocatalysts for the Alkaline Hydrogen Evolution Reaction

Donghwan Yoon; Jaeyoung Lee; Bora Seo; Byeongyoon Kim; Hionsuck Baik; Sang Hoon Joo; Kwangyeol Lee

doi:10.1002/smll.201700052

Cactus-Like Hollow Cu_2-_x S@Ru Nanoplates as Excellent and Robust Electrocatalysts for the Alkaline Hydrogen Evolution Reaction

Small. 2017 Aug;13(29). doi: 10.1002/smll.201700052. Epub 2017 Jun 8.

Authors

Donghwan Yoon^{1

2}, Jaeyoung Lee², Bora Seo³, Byeongyoon Kim², Hionsuck Baik⁴, Sang Hoon Joo^{3

5}, Kwangyeol Lee^{1

2}

Affiliations

¹ Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science (IBS), Seoul, 02841, Korea.
² Department of Chemistry, Korea University, Seoul, 02841, Korea.
³ Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Korea.
⁴ Korea Basic Science Institute (KBSI), Seoul, 02841, Korea.
⁵ School of Energy and Chemical Engineering, UNIST, Ulsan, 44919, Korea.

PMID: 28594433
DOI: 10.1002/smll.201700052

Abstract

The development of Pt-free electrocatalysts for the hydrogen evolution reaction (HER) recently is a focus of great interest. While several strategies are developed to control the structural properties of non-Pt catalysts and boost their electrocatalytic activities for the HER, the generation of highly reactive defects or interfaces by combining a metal with other metals, or with metal oxides/sulfides, can lead to notably enhanced catalytic performance. Herein, the preparation of cactus-like hollow Cu_2-_x S@Ru nanoplates (NPs) that contain metal/metal sulfide heterojunctions and show excellent catalytic activity and durability for the HER in alkaline media is reported. The initial formation of Ru islands on presynthesized Cu_1.94 S NPs, via cation exchange between three Cu⁺ ions and one Ru³⁺ , induces the growth of the Ru phase, which is concomitant with the dissolution of the Cu_1.94 S nanotemplate, culminating in the formation of a hollow nanostructure with numerous thin Ru pillars. Hollow Cu_2-_x S@Ru NPs exhibit a small overpotential of 82 mV at a current density of -10 mA cm^-2 and a low Tafel slope of 48 mV dec^-1 under alkaline conditions; this catalyst is among state-of-the-art HER electrocatalysts in alkaline media. The excellent performance of hollow Cu_2-_x S@Ru NPs originates from the facile dissociation of water in the Volmer step.

Keywords: Ru; copper sulfide; hollow nanoplate; hydrogen evolution; porous.

Publication types

Research Support, Non-U.S. Gov't