Order-disorder engineering of RuO2 nanosheets towards pH-universal oxygen evolution

Research output: Journal Publications and ReviewsRGC 21 - Publication in refereed journalpeer-review

5 Scopus Citations
View graph of relations

Detail(s)

Original languageEnglish
Pages (from-to)2904-2912
Number of pages9
Journal / PublicationMaterials Horizons
Volume10
Issue number8
Online published10 May 2023
Publication statusPublished - 1 Aug 2023

Abstract

Ru-based electrocatalysts are considered promising anode catalysts towards water electrolysis due to their impressive activity under acidic conditions. Yet, caused by the collapse of the local crystalline domains and concurrent leaching of Ru species during the OER process, durability against structural degradation remains poor. Herein, we present an order-disorder structure optimization strategy, based on RuO2 nanosheets with well-defined amorphous-crystalline boundaries supported on carbon cloth (a/c-RuO2/CC), to effectively catalyze water oxidation, especially in the case of an acidic medium. Specifically, the as-prepared a/c-RuO2/CC sample has achieved a lower overpotential of 150 mV at 10 mA cm−2, a smaller Tafel slope of 47 mV dec−1, and a significantly higher durability with suppressed dissolution of Ru, with regard to its crystalline (c-RuO2/CC) and amorphous (a-RuO2/CC) counterparts. Computational simulations combined with experimental characterizations uncover that the construction of the structurally ordered-disordered boundary enables a weakened Ru-O covalency with regard to the ordered counterpart, which suppresses the leaching of active Ru species from the crystalline phase, thus enhances stability. An upshift of the d-band center in a/c-RuO2/CC relative to a-RuO2/CC reduces the energy barrier of the potential-determining step (*O → *OOH), thereby dramatically boosting activity. © 2023 The Royal Society of Chemistry.