Surface functionalization of nano MgO particles with nickel and cobalt

Abstract

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 HCl, and PdCl2 and HCl solutions, respectively. In electroless coating bath, nickel sulfate (NiSO4 center dot 6H(2)O), cobalt sulfate (CoSO4 center dot 6H(2)O), sodium hypophosphite (NaH2PO2 center dot H2O) and sodium citrate (Na3C6H5O7 center dot 5H(2)O) 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.