International audienceThis work investigates the deposition of Pt nanoparticles onto carbon aerogels (CA), derived from microcrystalline cellulose. Nanoparticles are synthesised via impregnating the CA with H2PtCl6 followed by reduction either under H2 at 300 C or in a basic NaBH4 solution. H2 reduction yields uniform Pt nanoparticles (average diameter < 2nm) dispersed over the CA surface as revealed by Transmission electron microscopy (TEM). Larger agglomerates can be seen in TEM images of NaBH4 reduced samples, which is confirmed by powder X-ray diffraction (XRD). A rotating disk electrode was employed to analyse the electrochemical properties of the Pt nanoparticles. The active area of the platinum nanoparticles was evaluated using hydro...