Preparation of PtcoreAgshell nanoparticles: Catalytic reduction of Ag⁺ ions by hydrogen

It is shown that the saturation of an aqueous solution containing silver ions with hydrogen in the presence of 9.5-nm platinum nanoparticles leads to the reduction of silver and the formation of PtcoreAgshell bimetal nanoparticles. An increase in the concentration of silver ions gives rise to a number of elementary silver layers that cover the platinum core. It is established that the concentration of silver ions does not substantially affect the rate of the formation of a silver shell on the surface of platinum nanoparticles.