Novel one-pot sol-gel synthesis route of Fe3C/few-layered graphene core/shell nanoparticles embedded in a carbon matrix

Alberto Castellano-Soria; Jesús López-Sánchez; Cecilia Granados-Miralles; María Varela; Elena Navarro; César González; Pilar Marín

doi:10.1016/j.jallcom.2022.163662

arXiv · 2309.15858

Novel one-pot sol-gel synthesis route of Fe3C/few-layered graphene core/shell nanoparticles embedded in a carbon matrix

Alberto Castellano-Soria·Jesús López-Sánchez·Cecilia Granados-Miralles·María Varela·Elena Navarro·César González·Pilar Marín

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Abstract

Fe3C/few-layered graphene core/shell nanoparticles embedded in a carbon matrix are synthesized by a novel two-step surfactant sol-gel strategy, where the processes of hydrolysis, polycondensation and drying take place in a one-pot. The present approach is based on the combined action of oleic acid and oleylamine, which act sterically on the precursor micelles when a densification temperature is performed in a reducing atmosphere. The structural and magnetic evolution of the formed compounds is investigated, ranging from iron oxides such as Fe3O4 and FeO, to the formation of pure Fe3C/C samples from 700 {\deg}C onwards. Interestingly, Fe3C nanoparticles with a size of ~20 nm crystallize immersed in the carbon matrix and the surrounding environment forms an oriented encapsulation built by few-layered graphene. The nanostructures show a saturation magnetization of ~43 emu/g and a moderate coercivity of ~500 Oe. Thereby, an innovative chemical route to produce single phase Fe3C nanoparticles is described, and an effective method of few-layered graphene passivation is proposed, yielding a product with a high magnetic response and high chemical stability against environmental corrosion.

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Alberto Castellano-Soria, Jesús López-Sánchez, Cecilia Granados-Miralles, María Varela, Elena Navarro, César González, Pilar Marín. 2023-09-24. Novel one-pot sol-gel synthesis route of Fe3C/few-layered graphene core/shell nanoparticles embedded in a carbon matrix. https://doi.org/10.1016/j.jallcom.2022.163662

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