Enhanced Protection of Carbon-Encapsulated Magnetic Nickel Nanoparticles through a Sucrose-Based Synthetic Strategy

We report an easy synthesis strategy for the incorporation of carbon-coated Ni nanoparticles within the pores of a highly porous carbon matrix. An advantageous feature of this process is that it is able to provide large amounts of magnetic Ni composite by means of an easy-to-follow one-pot reaction. While a typical chemical route based on a conventional pyrolysis procedure gives rise to NPs with Ni@NiO (core@shell structure), the addition of sucrose to the synthesis mixture and its subsequent transformation to carbon endows the Ni-NPs with an effective protection via the formation of a thin carbon layer around the metallic nanoparticles. This protective shell stabilizes the inserted metallic particles by preventing the aerial oxidation of Ni-NPs (i.e., NiO) and their dissolution in an aqueous acid environment. The macroscopic magnetization values of these nanocomposites (up to 6 emu/g) and their superparamagnetic behavior at room temperature allow them to be easily manipulated with conventional magnets. T...