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Title: Ruthenium/Carbon Nanocomposites for Efficient Hydrogen Electrocatalysis: Impacts of Halide Residues
Ruthenium has emerged as a promising substitute for platinum toward the hydrogen evolution/oxidation reaction (HER/HOR). Herein, ruthenium/carbon composites are prepared by magnetic induction heating (300 A, 10 s) of RuCl3, RuBr3or RuI3loaded on hollow N‐doped carbon cages (HNC). The HNC‐RuCl3‐300A sample consists of Ru nanoparticles (dia. 1.96 nm) and abundant Cl residues. HNC‐RuBr3‐300A possesses a larger nanoparticle size (≈19.36 nm) and lower content of Br residues. HNC‐RuI3‐300A contains only bulk‐like Ru agglomerates with a minimal amount of I residues, due to reduced Ru‐halide bonding interactions. Among these, HNC‐RuCl3‐300A exhibits the best HER activity in alkaline media, with a low overpotential of only −26 mV to reach 10 mA cm−2, even outperforming Pt/C, and can be used as the cathode catalyst for anion exchange membrane water electrolyzer (along with commercial RuO2as the anode catalyst), producing 0.5 A cm−2at 1.88 V for up to 100 h, a performance markedly better than that with Pt/C. HNC‐RuCl3‐300A also exhibits the best HOR activity, with a half‐wave potential (+18 mV) even lower than that of Pt/C (+35 mV). These activities are ascribed to the combined contributions of small Ru nanoparticles and Ru‐to‐halide charge transfer that weaken H adsorption.  more » « less
Award ID(s):
1900235
PAR ID:
10647086
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley
Date Published:
Journal Name:
ChemSusChem
Volume:
18
Issue:
15
ISSN:
1864-5631
Page Range / eLocation ID:
e202500802
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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