One-step controllable fabrication of 3D structured self-standing Al3Ni2/Ni electrode through molten salt electrolysis for efficient water splitting

Zhongsheng Hua, Xiaobin Wu, Zengli Zhu, Jiwen He, Shiwei He, Huan Liu, Liang Xu, Yongxiang Yang, Zhuo Zhao

Research output: Contribution to journalArticleScientificpeer-review

Abstract

Exploring more efficient and low-cost electrocatalysts to replace platinum (Pt) is highly desired to promote the practical hydrogen production through water splitting. Herein, a facile and effective strategy is proposed to fabricate self-standing Al3Ni2/Ni electrode with controlled phase composition and surface morphology, which is obtained by one-step electrochemical reduction of Al3+ on commercially available nickel in eutectic NaCl-KCl melt. Different from previously reported approaches, uniform Al3Ni2 monolith catalyst can directly grow onto Ni substrate. The deposit possesses unique three-dimensional (3D) cauliflower-like morphology comprising of nano- and microparticles due to the rapid nucleation rate during molten salt electrolysis. The as-fabricated Al3Ni2/Ni electrode can be directly used as the cathode to catalyze Hydrogen evolution reaction (HER). Impressively, it exhibits remarkable HER activity comparable to commercial Pt, including a low overpotential of 83.4 mV for a current density of 10 mA cm−2, a small Tafel slope of 40.7 mV dec-1, and excellent long-term stability over 36 h of continuous HER operation in 0.5 M H2SO4 solution. The intrinsic catalytic ability of Al3Ni2 with the unique hierarchical structure of nano/microsized grains can offer multiple effects, including massive exposed active sites, enhanced charge transfer and mass transport, and fast gas releasing that synergistically contribute to improving the electrocatalytic performance of HER. This work represents a highly promising approach to the design and one-step controllable fabrication of efficient and self-standing base metal electrode for electrocatalytic hydrogen production.

Original languageEnglish
Article number131743
Number of pages14
JournalChemical Engineering Journal
Volume427
DOIs
Publication statusPublished - 2022

Keywords

  • AlNi/Ni electrode
  • Electrocatalytic performance
  • Hydrogen evolution reaction
  • Molten salt electrolysis
  • Water splitting

Fingerprint

Dive into the research topics of 'One-step controllable fabrication of 3D structured self-standing Al<sub>3</sub>Ni<sub>2</sub>/Ni electrode through molten salt electrolysis for efficient water splitting'. Together they form a unique fingerprint.

Cite this