Synthesis of platinum nanoparticles in microemulsions and their catalytic activity for the oxidation of carbon monoxide

Platinum nanoparticles have been prepared by the reduction of metal ions with hydrazine in oil–water microemulsions consisting of sodium bis(2-ethylhexyl)sulphosuccinate (AOT)+cyclohexane+water of varying composition. The catalytic efficiency of the synthesized metal nanoclusters has been tested for oxidation of carbon monoxide. Effects of the nature of the platinum salt, [H2O]/[surfactant] ratio in the microemulsions and the addition of polymers on the catalytic efficiency of the synthesized metal nanoparticles have been investigated. Catalytic oxidation of CO gas was carried out in a vertical quartz tube connected to a quadrupole mass spectrometer. Whereas, using pure alumina as a catalyst, complete conversion of CO to CO2 was observed at 325 °C, platinum nanoparticles adsorbed on alumina was found to carry out such conversion at 145 °C.