Materials Research Express, cilt.6, sa.8, 2019 (SCI-Expanded)
In the present work, nano magnesium oxide (MgO) particles were coated with nickel and cobalt to increase surface activity of the nano particles. Prior to coating process, surfaces of MgO particles were sensitized and then activated using SnCl2 and HCI, and PdCl2 and HCI solutions, respectively. In electroless coating bath, nickel sulfate (NiSO4•6H2O), cobalt sulfate (CoSO4.6H2O), sodium hypophosphite (NaH2PO2•H2O) and sodium citrate (Na3C6H5O7.5H2O) were used as Ni++ and Co++ sources, reducing agent and complexing agent, respectively. The morphology, characterization and chemical composition of coating were characterized by Raman spectroscopy, scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS), x-ray diffraction and transmission electron microscope (TEM). Results showed that particle surfaces were coated by nickel and cobalt, and nickel deposition ratio compared to cobalt deposition was more successfully carried out. It was worthily noted that size of samples with coated nickel and cobalt did not converted from nano scale to micro scale, and the mobility and electro-kinetic nature of particles in electrolyte have an important effect on deposition mechanism of coatings.