Synthesis of carbon embedded MFe2O4 (M = Ni, Zn and Co) nanoparticles as efficient hydrogenation catalysts

Abstract

Successful synthesis of stable MFe₂O₄ nanoparticles@C has been realized by applying the novel concept of using levulinic acid possessing carboxyl and carbonyl groups to facilitate the interaction with metal ions (M²⁺ and Fe³⁺) and the carbon source (phloroglucinol) in the sol–gel polymerization method. All the samples have been characterized by XRD, SEM, FT-IR, TEM, HRTEM, ICP-AES, CHNS, and N₂ adsorption–desorption, and were studied for their performance towards hydrogenation reaction of styrene. Out of three samples NiFe₂O₄ gave excellent selective hydrogenation activity of styrene to ethyl benzene (100% conversion and 100% selectivity). Optimal production of ethyl benzene over NiFe₂O₄ nanoparticles@C has been established at 80 °C reaction temperature after 24 h reaction time under 40 bar hydrogen pressure.