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  • Ru-CoO heterostructured nanoparticles supported on nitrogen and sulfur codoped graphene nanosheets as effective electrocatalysts for hydrogen evolution reaction in alkaline media
Title: Ru-CoO heterostructured nanoparticles supported on nitrogen and sulfur codoped graphene nanosheets as effective electrocatalysts for hydrogen evolution reaction in alkaline media
Production of clean hydrogen energy from water splitting is vital for the future fuel industry, and nanocomposites have emerged as effective catalysts for the hydrogen evolution reaction (HER). In this study, Ru-CoO@SNG nanocomposites are prepared by controlled pyrolysis where Ru-CoO heterostructured nanoparticles are supported on nitrogen and sulfur codoped graphene oxide nanosheets. With a large surface area, the obtained composites exhibit a remarkable electrocatalytic activity toward HER in 1.0 M KOH with an overpotential of only −90 mV to reach the current density of 10 mA cm−2 , in comparison to −60 mV for commercial Pt/C benchmark, along with high stability. Mechanistically, codoping of sulfur and nitrogen facilitates the dispersion of the nanoparticles, and the formation of Ru-CoO heterostructures increases the active site density, reduces the electron-transfer kinetics and boosts the catalytic performance. Results from this study highlight the unique potential of structural engineering in enhancing the electrocatalytic performance of heterostructured nanocomposites.  more » « less
Award ID(s):
1900235
NSF-PAR ID:
10482226
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Journal of Electroanalytical Chemistry
Volume:
932
Issue:
C
ISSN:
1572-6657
Page Range / eLocation ID:
117272
Subject(s) / Keyword(s):
["Sulfur,nitrogen-codoped graphene","Ruthenium","Cobalt oxide","Heterostructure","Hydrogen evolution reaction"]
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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