Cobalt-Iron Oxide Nanoarrays Supported on Carbon Fiber Paper with High Stability for Electrochemical Oxygen Evolution at Large Current Densities

Zhiguo Ye; Chunlin Qin; Guang Ma; Xinyuan Peng; Tao Li; Duosheng Li; Zhong Jin

doi:10.1021/acsami.8b15357

Cobalt-Iron Oxide Nanoarrays Supported on Carbon Fiber Paper with High Stability for Electrochemical Oxygen Evolution at Large Current Densities

ACS Appl Mater Interfaces. 2018 Nov 21;10(46):39809-39818. doi: 10.1021/acsami.8b15357. Epub 2018 Nov 6.

Authors

Zhiguo Ye¹, Chunlin Qin¹, Guang Ma², Xinyuan Peng¹, Tao Li¹, Duosheng Li¹, Zhong Jin³

Affiliations

¹ School of Material Science and Engineering , Nanchang Hangkong University , Nanchang 330063 , China.
² Global Energy Interconnection Research Institute Co., Ltd. , Beijing 102209 , China.
³ Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing , Jiangsu 210023 , China.

PMID: 30362701
DOI: 10.1021/acsami.8b15357

Abstract

Here, we demonstrate that nonprecious CoFe-based oxide nanoarrays exhibit excellent electrocatalytic activity and superior stability for electrochemical oxygen evolution reaction (OER) at large current densities (>500 mA cm^-2). Carbon fiber paper (CFP) with three-dimensional macroporous structure, excellent corrosion resistance, and high electrical properties is used as the support material to prevent surface passivation during the long-term process of OER. Through a facile method of hydrothermal synthesis and thermal treatment, vertically aligned arrays of spinel Co _xFe_{3- x}O₄ nanostructures are homogeneously grown on CFP. The morphology and the Fe-doping content of the CoFe oxide nanoarrays can be controlled by the Fe³⁺ concentration in the precursor solution. The arrays of CoFe oxide nanosheets (NSs) grown on CFP (Co_2.3Fe_0.7O₄-NSs/CFP) deliver lower Tafel slope (34.3 mV dec^-1) than CoFe oxide nanowire (NW) arrays grown on CFP (Co_2.7Fe_0.3O₄-NWs/CFP) in alkaline solution, owing to higher Fe-doping content and larger effective specific surface area. The Co_2.3Fe_0.7O₄-NSs/CFP electrode exhibits excellent stability for OER at large current densities in alkaline solution. Moreover, the morphology and structure of CoFeO nanoarrays are well preserved after long-term testing, indicating the high stability for OER.

Keywords: cobalt-iron oxide; nanoarray; oxygen evolution reaction; stability; water splitting.