There has been increasing demand to develop sustainable energy sources with high energy-conversion efficiency. Direct ethanol fuel cells (DEFCs) are one type of clean power source that is promising for a variety of applications. DEFCs typically consist of an anodic chamber that oxidizes ethanol and transfers electrons via an external circuit to a cathodic chamber that reduces oxygen. Nobel metals such as platinum (Pt) and palladium (Pd) are often used as electrocatalysts for the ethanol oxidation reaction (EOR) in the DEFC anode because of their intrinsic electrochemical properties. Unfortunately, cost and poor market supply require manipulating structural features of catalysts including shapes, sizes, and compositions to achieve optimal benefit from Pt and Pd. Further, to realize the utility of DEFCs in these applications, they must be cheap, lightweight, highly efficient, and stable over long operation lifetimes. We have developed DEFCs with enhanced electrochemical performance using three different electrocatalysts (Pt, Pd, and Pd-Pt core-shell nanoparticles) supported on graphene-coated carbon nanotube aerogels. These three-dimensional, porous aerogels are lightweight, and provide easy transport pathways for fuel and ions. The ultrahigh surface area of the aerogels allows deposition of small catalyst nanoparticles, while the graphene coating hinders coarsening of the nanoparticles during operation, improving the DEFC lifetime. The catalysts are spherical nanoparticles of diameter ≈ 5 nm (Pt), ≈ 8 nm (Pd), and ≈ 9 nm (Pd-Pt core-shell). The current densities of our DEFCs in alkaline media are ≈ 118 mA/cm² with Pt, ≈ 150 mA/cm² with Pd, and ≈ 283 mA/cm² with Pd-Pt core-shell electrocatalysts, which are at least an order of magnitude larger than that of DEFCs that utilize commercially available electrodes, typically comprised of Pd nanoparticles supported on carbon black. Further, the performance of our DEFCs shows minimal degradation of 30–60% over 1,000 cycles. This work has been partially supported by the NSF through Grant CMMI 1335417 and US Army Research Office through grant W911NF-14-1-0651.