Synthesis of the oleylamine coated mesoporous Fe3O4 nanospheres and their application towards the efficient chemical fixation of carbon dioxide

Abstract

The present work reports the successful coating of Fe3O4 nanospheres with oleylamine utilizing a single-step solvothermal technique and its application to carbon dioxide's capture and chemical fixation. The existence of the pure cubic spinel phase of Fe3O4 was established by X-ray diffraction. Fourier transform infrared spectroscopy revealed vibrations corresponding to the oleylamine structure, affirming the coating of oleylamine on Fe3O4 nanospheres. X-ray photoelectron spectroscopy further confirmed the presence of oleylamine on the Fe3O4 surface, along with the constituent elements Fe and O. The nanospheres exhibited a spherical shape with an average diameter of ∼17 nm, shown by morphological investigations. Magnetic properties exhibited a Verwey transition at ∼114 K and a saturation magnetization of ∼60 emu/g. The surface area measurements revealed a pore volume of 0.0717 ccg−1 and surface area of 30.558 m2g-1. The existence of oleylamine on the surface of Fe3O4 nanospheres facilitated the capture of CO2 through chemisorption due to the amine group's high selectivity and the nanospheres' large surface area. In the presence of styrene oxide and tetra-n-hexyl ammonium bromide (THAB), the oleylamine-coated Fe3O4 nanospheres successfully converted CO2 to styrene carbonate. The magnetic core and high thermal stability of the material make it suitable for recyclability for the fixation of CO2 into products with added value. This work presents a promising approach for CO2 capture and utilization using Fe3O4 nanospheres coated with oleylamine, with potential applications in carbon capture and utilization technologies.