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Title: Structure-controlled graphene electrocatalysts for high-performance H 2 O 2 production
Metal-free carbon materials have emerged as cost-effective and high-performance catalysts for the production of hydrogen peroxide (H 2 O 2 ) through the two-electron oxygen reduction reaction (ORR). Here, we show that 3D crumpled graphene with controlled oxygen and defect configurations significantly improves the electrocatalytic production of H 2 O 2 . The crumpled graphene electrocatalyst with optimal defect structures and oxygen functional groups exhibits outstanding H 2 O 2 selectivity of 92–100% in a wide potential window of 0.05–0.7 V vs. reversible hydrogen electrode (RHE) and a high mass activity of 158 A g −1 at 0.65 V vs. RHE in alkaline media. In addition, the crumpled graphene catalyst showed an excellent H 2 O 2 production rate of 473.9 mmol gcat −1 h −1 and stability over 46 h at 0.4 V vs. RHE. Moreover, density functional theory calculations revealed the role of the functional groups and defect sites in the two-electron ORR pathway through the scaling relation between OOH and O adsorption strengths. These results establish a structure-mechanism-performance relationship of functionalized carbon catalysts for the effective production of H 2 O 2 .  more » « less
Award ID(s):
1751693
PAR ID:
10424629
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Energy & Environmental Science
Volume:
15
Issue:
7
ISSN:
1754-5692
Page Range / eLocation ID:
2858 to 2866
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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