Synthesis, structural and magnetic properties of NiO nanospheres and rGO-NiO nanocomposites and observing magnetocaloric effect in rGO-NiO nanocomposites

摘要

NiO nanospheres and NiO nanospheres deposited on rGO nanosheets i.e., rGO-NiO nanocomposites have been synthesized using in-situ solvothermal method. The crystal structures, phases, and morphologies of the synthesized samples have been confirmed by XRD, Raman, and TEM measurements. The detailed information regarding chemical bonding, identification of the constituent elements and their binding chemical states in the synthesized nanocomposites were revealed using FT-IR, EDX and XPS measurements. The magnetic behavior of the synthesized samples as a function of applied magnetic field and temperature was examined using VSM. The observed value of magnetization significantly represents stable magnetic ordering and magnetic transitions in the prepared samples. The calculated values of ΔS_m~(max)(1.03 J/Kg/K) and RC (28 J/Kg) indicate the presence of an inherent magnetocaloric effect in the synthesized rGO-NiO nanocomposites.