< Back to previous page

Publication

Revealing pH-dependent activities and surface instabilities for Ni-based electrocatalysts during the oxygen evolution reaction

Journal Contribution - Journal Article

Multiple electrochemical processes are involved at the catalyst/electrolyte interface during the oxygen evolution reaction (OER). With the purpose of elucidating the complexity of surface dynamics upon OER, we systematically studied two Ni-based crystalline oxides (LaNiO3−δ and La2Li0.5Ni0.5O4) and compared them with the state-of-the-art NiFe (oxy)hydroxide amorphous catalyst. Electrochemical measurements such as rotating ring disk electrode (RRDE) and electrochemical quartz microbalance microscopy (EQCM) coupled with a series of physical characterizations including transmission electron microscopy (TEM) and X-ray absorption spectroscopy (XAS) were conducted to unravel the exact pH effect on both the OER activity and the catalyst stability. We demonstrate that for Ni-based crystalline catalysts the rate for surface degradation depends on the pH and is greater than the rate for surface reconstruction. This behavior is unlike that for the amorphous Ni oxyhydroxide catalyst, which is found to be more stable and pH-independent.
Journal: ACS energy letters
ISSN: 2380-8195
Volume: 3
Pages: 2884 - 2890
Publication year:2018
Keywords:A1 Journal article
BOF-keylabel:yes
BOF-publication weight:10
CSS-citation score:1
Authors:International
Authors from:Higher Education
Accessibility:Open