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arXiv · 2505.13739

Magnetic field-enhanced two-electron oxygen reduction reaction using CeMnCo nanoparticles supported on different carbonaceous matrices

Caio Machado Fernandes·Joao Paulo C. Moura·Aline B. Trench·Odivaldo C. Alves·Yutao Xing·Marcos R. V. Lanza·Julio Cesar M. Silva·Mauro C. Santos
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Abstract

The current study illustrates the successful synthesis of Ce$_{1.0}$Mn$_{0.9}$Co$_{0.1}$ nanoparticles, characterized through XRD, EPR, magnetization curves, and TEM/HRTEM/EDX analyses. These nanoparticles were then loaded into the carbon Vulcan XC72 and the carbon Printex L6 matrices in varying amounts (1, 3, 5, and 10% w/w) via wet impregnation method to fabricate electrocatalysts for the 2-electron ORR. Before experimentation, the material was characterized via XPS and contact angle measurements. The electrochemical results produced significant findings, indicating that the electrocatalysts with the nanostructures modifying both carbon blacks notably augmented currents in rotating ring-disk electrode measurements, signifying enhanced selectivity for H$_2$O$_2$ production. Moreover, our research underscored the significant impact of Magnetic Field-Enhanced Electrochemistry, employing a constant magnetic field strength of 2000 Oe, on 2-electron ORR experiments. Particularly noteworthy were the observed results surpassing the ones without the magnetic field, demonstrating heightened currents and improved selectivity for H$_2$O$_2$ production (more than 90 %) facilitated by CeMnCo nanoparticles. These significant findings in electrocatalytic efficiency have practical implications, suggesting the potential for developing more efficient and selective catalysts for the 2-electron ORR.

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Caio Machado Fernandes, Joao Paulo C. Moura, Aline B. Trench, Odivaldo C. Alves, Yutao Xing, Marcos R. V. Lanza, Julio Cesar M. Silva, Mauro C. Santos. 2025-05-19. Magnetic field-enhanced two-electron oxygen reduction reaction using CeMnCo nanoparticles supported on different carbonaceous matrices. https://arxiv.org/abs/2505.13739

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