Synthesis and Catalytic Properties of Ni©Ag Bimetallic Nanostructures

Abstract

Magnetic bimetallic Ni©Ag nanostructures have been synthesized by cementation of silver with nickel nanoparticles at different starting ratios Ni/Ag. It was found that the obtained precipitates are well separated from the reaction mixture by applying an external magnetic field without any losses of the target products. Kinetics of the cementation was monitored by direct potentiometry technique and it was observed that the atomic ratios of Ni/Ag in the obtained products do not depend on the starting concentration of Ag+. Using transmission electron microscopy, it was found that at a low concentration of Ag+in the reaction mixture silver crystallized in the form of nanoplates and at high concentration of Ag+ the formation of silver rods was observed. In addition, the plate-like Ni©Ag nanostructures have been tested as possible catalysts for oxidation of organic substrates with molecular oxygen. It was found that the addition of Ni©Ag to the reaction mixture accelerates the reaction of the initiated liquid-phase solvent free oxidation of cumene by 1.4 – 2 times.