Microwave-assisted synthesis of carbon-supported Pt nanoparticles for their use as electrocatalysts in the oxygen reduction reaction and hydrogen evolution reaction

Pt nanoparticles were incorporated on carbon black (Vulcan XC-72R) and an activated carbon (F400) using a fast and efficient microwave method. For the preparation, a Pt solution was contacted with the corresponding carbon sample and heated up to 110 degrees C in a microwave oven using an optimised heating rate. TEM images revealed that the carbon-supported Pt nanoparticles had a small average particle size and high dispersion. These Pt-based electrocatalysts showed both high electrocatalytic activity and selectivity towards the 4-electron pathway for the oxygen reduction reaction (ORR) in acid and alkaline media. In addition, they presented excellent stability and resistance to CO poisoning. Moreover, the as-prepared electrocatalysts exhibited outstanding electrocatalytic behavior for the hydrogen evolution reaction (HER). It should be highlighted that, even though our Pt-based electrocatalysts have much lower loadings than that of the commercial Pt/C sample (used as reference), the electroactive surface areas of as-prepared electrocatalysts were higher compared to the reference electrocatalyst. Such small and well-dispersed Pt NPs with an enhanced electroactive surface area and strong interaction with the carbon support, led to an improvement of the current density normalised by Pt loading (A gPt 1).