Enhanced ammonia electro-oxidation reaction on platinum-iron oxide catalyst assisted by MagnetoElectroCatalysis

Caio Machado Fernandes; Eduardo M. Rodrigues; Odivaldo C. Alves; Flavio Garcia; Yutao Xing; Mauro C. Santos; Julio Cesar M. Silva

arXiv · 2505.13759

Enhanced ammonia electro-oxidation reaction on platinum-iron oxide catalyst assisted by MagnetoElectroCatalysis

Caio Machado Fernandes·Eduardo M. Rodrigues·Odivaldo C. Alves·Flavio Garcia·Yutao Xing·Mauro C. Santos·Julio Cesar M. Silva

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Abstract

Ammonia poses significant environmental challenges due to its role in water pollution, contributing to eutrophication and several detrimental environmental and ecological issues. Addressing the efficient removal or conversion of ammonia is, therefore, critical. Among various methods, the ammonia electro-oxidation reaction stands out due to its potential for direct energy conversion and environment remediation. Here, we synthesize platinum-iron oxide magnetic nanoparticles (Pt-MNP) as electrocatalysts and apply an alternating magnetic field (AMF) to enhance their activity.. The AMF generates localized heat via Néel relaxation, accelerating ammonia oxidation kinetics at the catalytic surface.. Compared to conventional electro-oxidation methods, this technique demonstrates superior efficiency and stability, offering a promising alternative for ammonia treatment. This work uses the concept of MagnetoElectroCatalysis, showcasing the synergy between magnetic fields and the electrochemical process, leveraging the AMF to induce localized heating within the nanocatalyst, thereby improving its catalytic activity as shown in cyclic voltammetry and chronoamperometry experiments. By combining nanocatalyst design with innovative AMF application, this study provides a new avenue for enhancing electrochemical reactions, with broad implications for environmental remediation and sustainable energy solutions.

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Caio Machado Fernandes, Eduardo M. Rodrigues, Odivaldo C. Alves, Flavio Garcia, Yutao Xing, Mauro C. Santos, Julio Cesar M. Silva. 2025-05-19. Enhanced ammonia electro-oxidation reaction on platinum-iron oxide catalyst assisted by MagnetoElectroCatalysis. https://arxiv.org/abs/2505.13759

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