In Situ Activated Co_3–xNi_xO₄ as a Highly Active and Ultrastable Electrocatalyst for Hydrogen Generation

Authors

Kailu Guo, Lanzhou University
Yantao Wang, Lanzhou University
Junfeng Huang, Lanzhou University
Min Lu, Lanzhou University
Hua Li, Lanzhou University
Yong Peng, Lanzhou University
Pinxian Xi, Lanzhou University
Haoli Zhang, Lanzhou University
Jier Huang, Marquette UniversityFollow
Siyu Lu, Zhengzhou University
Cailing Xu, Lanzhou University

Document Type

Article

Publication Date

7-2021

Publisher

American Chemical Society

Source Publication

ACS Catalysis

Source ISSN

2155-5435

Abstract

The spinel Co₃O₄ has emerged as a promising alternative to noble-metal-based electrocatalysts for electrochemical water electrolysis in alkaline medium. However, pure Co₃O₄, despite having high activity in anodic water oxidation, remains inactive toward the hydrogen evolution reaction (HER). Here, a Ni-doped Co₃O₄(Co_3–xNi_xO₄) prepared by a simple method exhibits favorable HER activity and stability (>300 h, whether in 1 M KOH or the realistic 30 wt % KOH solution) after in situ electrochemical activation, outperforming almost all of the oxide-based electrocatalysts. More importantly, using the combination of in situ Raman spectroscopy and multiple high-resolution electron microscopy techniques, it is identified that the surface of Co_3–xNi_xO₄ crystals is reduced into intertwined Co_yNi_1–yO nanoparticles with highly exposed {110} reactive planes. Density functional theory calculations further prove that the Ni-doped CoO component in Co_yNi_1–yO plays a major role during the alkaline HER, because the introduction of Ni atoms into Co–O octahedra can optimize the electrical conductivity and tailor the adsorption/desorption free energies of H_ad and OH_ad intermediates.

Comments

Accepted version. ACS Catalysis, Vol. 11, No. 13 (July 2, 2021): 8174-8182. DOI. © 2021 American Chemical Society. Used with permission.

Recommended Citation

Guo, Kailu; Wang, Yantao; Huang, Junfeng; Lu, Min; Li, Hua; Peng, Yong; Xi, Pinxian; Zhang, Haoli; Huang, Jier; Lu, Siyu; and Xu, Cailing, "In Situ Activated Co_3–xNi_xO₄ as a Highly Active and Ultrastable Electrocatalyst for Hydrogen Generation" (2021). Chemistry Faculty Research and Publications. 1048.
https://epublications.marquette.edu/chem_fac/1048