“…1 A variety of transition metals have been used to synthesize metal NPs, including gold, 2 nickel, 3 iron (particularly iron oxide), 4 platinum, 5 cobalt, 6 titanium, 7 ruthenium, 8 rhodium, 9 osmium, 10 silver 11 and palladium. 12 In addition, particles consisting of alloys of noble metals, including platinum-palladium, 13 platinum-gold, 14 palladium-gold 15 and palladium-silver 16 have been prepared.…”