Pt nanoparticles were synthesized according to a modified literature procedure. H2PtCl6 (0.9 mL, 8 wt. % solution) was added to water (36 mL). Water (464 mL) was heated to 95 °C and the H2PtCl6 solution was added with stirring followed by 0.05 wt. % citric acid / 1 wt. % trisodium citrate dihydrate aqueous solution (11 mL) followed by sodium borohydride (37 mg) in 0.05 wt.% citric acid / 1 wt. % trisodium citrate dihydrate aqueous solution (11 mL). The solution was stirred at 100 °C for 10 minutes before cooling to room temperature.