Porous carbon electrodes provide structure and function for energy storage and conversion devices such as batteries, electrochemical capacitors, and fuel cells. Ultraporous, high-surface-area carbon nanofoams with submicrometer pore networks interconnected in three dimensions (3D) offer increased versatility as conductive scaffolds, particularly because the surface of the carbon network can be readily modified with energy-storing or catalytic moieties. We modify the surfaces of our carbon nanofoams with thiophene-like "hooks" to anchor pre-formed Pd or Au nanoparticles, yielding electroactive carbon nanostructures containing less than 1 wt% of well-dispersed precious metal colloids. Gold, formerly regarded as a poor catalytic noble metal, now well known for its use as a gas-phase oxidation catalyst when sized on the nanoscale, has recently come into interest for its potential in fuel-cell technology and sensors. The nanoparticle-functionalized nanofoams are characterized in terms of their electrochemical accessibility for the ethanol oxidation reaction and the role of the thiophene linker. We observe that colloidal gold nanoparticles adsorb at both the boundary surface and interior walls of thiophenylated carbon nanofoams, allowing us to probe whether the metal nanoparticles chemically bind at the heterocyclic sulfur moieties in the carbon walls or if they are physically entrained within the nanometric pores, voids, nooks, and crannies of the composite.