Origin of Disparities in Water Oxidation between Amorphous and Crystalline ElectrocatalystsShow others and affiliations
2025 (English)In: ACS Catalysis, E-ISSN 2155-5435, Vol. 15, no 4, p. 3256-3266Article in journal (Refereed) Published
Abstract [en]
Amorphous catalysts behave differently in oxygen evolution reaction (OER) performance compared with their crystalline counterparts; however, the origin of this disparity is still ambiguous. Herein, amorphous and crystalline CoOOH are invoked as the model catalysts to explore the origin of their difference in the OER performance. Electrochemical measurement results demonstrate that the amorphous CoOOH has more active sites in quantity but lower intrinsic activity per site than the crystalline CoOOH in the initial stage of the OER. Nevertheless, the intrinsic activity per site of the amorphous CoOOH continues to increase until a level close to that of the crystalline CoOOH is achieved when the OER proceeds. On the basis of operando characterizations and electrochemical analysis, a dual-pathway model of reconstruction is proposed to explain the catalytic behaviors of these CoOOH. The intrinsic activity of catalysts is dominated by two reconstruction pathways. The distinction of intrinsic activity between the amorphous and crystalline CoOOH is caused by the different proportions of each pathway included in OER. Moreover, the quenching reaction between Co4+ and the oxygen vacancy in the amorphous catalyst motivates the surface reconstruction and subsequently promotes the crystallinity. This study provides a perspective for understanding the surface reconstruction mechanism in the OER.
Place, publisher, year, edition, pages
American Chemical Society (ACS) , 2025. Vol. 15, no 4, p. 3256-3266
Keywords [en]
Amorphous CoOOH, Oxygen Evolution Reaction, Oxygen Vacancy, Reconstruction Pathway, Surface Reconstruction
National Category
Organic Chemistry
Identifiers
URN: urn:nbn:se:kth:diva-385754DOI: 10.1021/acscatal.4c07903ISI: 001416489300001Scopus ID: 2-s2.0-85217121315OAI: oai:DiVA.org:kth-385754DiVA, id: diva2:2087142
Note
QC 20260717
2026-07-172026-07-172026-07-17Bibliographically approved