Abstract Ruthenium has been hailed as a competitive alternative for platinum toward hydrogen evolution reaction (HER), a critical process in electrochemical water splitting. In this study, we successfully prepare metallic Ru nanoparticles supported on carbon paper by utilizing a novel magnetic induction heating (MIH) method. The samples are obtained within seconds, featuring a Cl‐enriched surface that is unattainable via conventional thermal annealing. The best sample within the series shows a remarkable HER activity in both acidic and alkaline media with an overpotential of only ‐23 and ‐12 mV to reach the current density of 10 mA/cm2, highly comparable to that of the Pt/C benchmark. Theoretical studies based on density functional theory show that the excellent electrocatalytic activity is accounted by the surface metal‐Cl species that facilitate charge transfer and downshift the d‐band center. Results from this study highlight the unique advantages of MIH in rapid sample preparation, where residual anion ligands play a critical role in manipulating the electronic properties of the metal surfaces and the eventual electrocatalytic activity.
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Catalytic Reaction Triggered by Magnetic Induction Heating Mechanistically Distinguishes Itself from the Standard Thermal Reaction
As a recent advancement in reaction engineering, magnetic induction heating (MIH) is utilized to initiate the intended reactions by enabling the self-heating of the ferromagnetic catalyst particles. While MIH can be energy-efficient and industrially scalable, its full potential has been underappreciated in catalysis because of the perception that MIH is merely an alternative heating approach. Unexpectedly, we show that the MIH-triggered reaction could go beyond standard thermal catalysis. Specifically, by probing the representative Pt/Fe3O4 catalysts with CO oxidation in both thermal and MIH modes with consistent temperature profiles and catalyst structures, we found that the MIH mode boosts the reactivity more than 25 times by modifying Pt−FeOx interfacial synergies and promoting facile oxidation of the adsorbed carbonyl species by atomic oxygen. As we preliminarily observed, this beneficial MIH catalysis can be translational to other thermal reactions, potentially paving the way to launch MIH catalysis as a distinct reaction category.
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- Award ID(s):
- 2146591
- PAR ID:
- 10554420
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Catalysis
- Volume:
- 14
- Issue:
- 6
- ISSN:
- 2155-5435
- Page Range / eLocation ID:
- 4008 to 4017
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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