Anchoring Ni/NiO heterojunction on freestanding carbon nanofibers for efficient electrochemical water oxidation

Chen Liang; Keyu Wang; Fang Xu; Yixing Wang; Shiyi Li; Kai Qu; Linfeng Lei; Linzhou Zhuang; Zhi Xu

doi:10.1016/j.jcis.2022.07.013

Anchoring Ni/NiO heterojunction on freestanding carbon nanofibers for efficient electrochemical water oxidation

J Colloid Interface Sci. 2022 Nov 15:626:995-1002. doi: 10.1016/j.jcis.2022.07.013. Epub 2022 Jul 5.

Authors

Chen Liang¹, Keyu Wang¹, Fang Xu¹, Yixing Wang¹, Shiyi Li¹, Kai Qu¹, Linfeng Lei¹, Linzhou Zhuang², Zhi Xu³

Affiliations

¹ State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China.
² State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China. Electronic address: lzzhuang@ecust.edu.cn.
³ State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China. Electronic address: zhixu@ecust.edu.cn.

PMID: 35839680
DOI: 10.1016/j.jcis.2022.07.013

Abstract

Rational design of low-cost and efficient electrocatalyst for the anodic oxygen evolution reaction (OER) to replace noble-metal-based catalysts is greatly desired for the large-scale application of water electrocatalysis. And compared with the conventional powdery catalysts, the freestanding electrode architecture is more attractive owing to the enhanced kinetics and stability. In this work, we report an electrospinning-carbonization-post oxidation strategy to develop the freestanding N-doped carbon nanofibers anchored with Ni/NiO nanoparticles (denoted as Ni/NiO-NCNFs) as efficient OER electrocatalyst. In the synthesized Ni/NiO-NCNFs, the conductive ultrathin carbon layer could promote electron transfer and thus improve the electrocatalytic activity. Meanwhile, the ratio between Ni and NiO could be regulated by tuning the oxidation duration, so as to optimize the adsorption energy of intermediates and improve the OER activity. The Ni/NiO-NCNFs prepared with the oxidation time of 3 h exhibit a promising OER activity and long-term operation durability in 0.1 M KOH solution, requiring an overpotential as small as 153 mV to achieve a current density of 10 mA cm^-2. Its overpotential is far lower than that of the reported OER catalysts. This work offers an efficient pathway to develop low-cost and highly active freestanding transitional metal-based OER electrocatalyst for potential renewable electrochemical energy conversion.

Keywords: Electrospinning; N-doped carbon nanofibers; Ni/NiO catalysts; Oxygen evolution reaction; Self-standing.