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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 .
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This content will become publicly available on April 26, 2025
A Non‐Macrocycle Thiolate‐Based Cobalt Catalyst for Selective O 2 Reduction into H 2 O
Abstract The reduction of dioxygen to produce selectively H2O2or H2O is crucial in various fields. While platinum‐based materials excel in 4H+/4e−oxygen reduction reaction (ORR) catalysis, cost and resource limitations drive the search for cost‐effective and abundant transition metal catalysts. It is thus of great importance to understand how the selectivity and efficiency of 3d‐metal ORR catalysts can be tuned. In this context, we report on a Co complex supported by a bisthiolate N2S2‐donor ligand acting as a homogeneous ORR catalyst in acetonitrile solutions both in the presence of a one‐electron reducing agent (selectivity for H2O of 93 % and TOFi=3 000 h−1) and under electrochemically‐assisted conditions (0.81 V <η<1.10 V, selectivity for H2O between 85 % and 95 %). Interestingly, such a predominant 4H+/4e−pathway for Co‐based ORR catalysts is rare, highlighting the key role of the thiolate donor ligand. Besides, the selectivity of this Co catalyst under chemical ORR conditions is inverse with respect to the Mn and Fe catalysts supported by the same ligand, which evidences the impact of the nature of the metal ion on the ORR selectivity.
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- Award ID(s):
- 2154955
- PAR ID:
- 10525579
- Publisher / Repository:
- European Chemical Societies Publishing
- Date Published:
- Journal Name:
- ChemCatChem
- ISSN:
- 1867-3880
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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