Aerogel and metallic compositions
Metallic aerogel compositions comprising an aerogel, e.g., RF or carbon aerogel, having metallic particles dispersed on its surface are disclosed. The aerogel compositions can have a uniform distribution of small metallic particles, e.g., 1 nanometer average particle diameter. Also disclosed are processes for making the aerogel compositions comprising contacting an aerogel with a supercritical fluid containing a metallic compound. The aerogel compositions are useful, for example in the manufacture of fuel cell electrodes.
1. A composition comprising an aerogel having a pore volume of at least 0.5 cm 3 /g, as determined using a nitrogen adsorption/desorption technique or equivalent, and metallic particles dispersed on a surface of said aerogel such that said composition comprises at least 10 wt. % of metallic particles based on the total weight of the composition, wherein said metallic particles include platinum and wherein said metallic particles having an average particle diameter of about 2.5 nanometers or less.
2. The composition of claim 1 , wherein said aerogel is a carbon aerogel.