Manipulating the Microenvironment of Single Atoms by Switching Support Crystallinity for Industrial Hydrogen Evolution.
Angew Chem Int Ed Engl
; 63(7): e202317220, 2024 Feb 12.
Article
em En
| MEDLINE
| ID: mdl-38153674
ABSTRACT
Modulating the microenvironment of single-atom catalysts (SACs) is critical to optimizing catalytic activity. Herein, we innovatively propose a strategy to improve the local reaction environment of Ru single atoms by precisely switching the crystallinity of the support from high crystalline and low crystalline, which significantly improves the hydrogen evolution reaction (HER) activity. The Ru single-atom catalyst anchored on low-crystalline nickel hydroxide (Ru-LC-Ni(OH)2 ) reconstructs the distribution balance of the interfacial ions due to the activation effect of metal dangling bonds on the support. Single-site Ru with a low oxidation state induces the aggregation of hydronium ions (H3 O+ ), leading to the formation of a local acidic microenvironment in alkaline media, breaking the pH-dependent HER activity. As a comparison, the Ru single-atom catalyst anchored on high-crystalline nickel hydroxide (Ru-HC-Ni(OH)2 ) exhibits a sluggish Volmer step and a conventional local reaction environment. As expected, Ru-LC-Ni(OH)2 requires low overpotentials of 9 and 136â
mV at 10 and 1000â
mA cm-2 in alkaline conditions and operates stably at 500â
mA cm-2 for 500â
h in an alkaline seawater anion exchange membrane (AEM) electrolyzer. This study provides a new perspective for constructing highly active single-atom electrocatalysts.
Texto completo:
1
Base de dados:
MEDLINE
Idioma:
En
Ano de publicação:
2024
Tipo de documento:
Article