A composition of nanoparticles of metal or an alloy or having a metal and alloy core with an oxide shell in admixture with platinum particles is useful as a component for electrodes. More particularly, such composition is useful as an electrode ink for the reduction of oxygen as well as the oxidation of hydrocarbon or hydrogen fuel in a direct oxidation fuel cell, such as, but not limited to, the direct methanol fuel cell. These electrodes encompass a catalyst ink containing platinum, the nanoparticles, and a conducting ionomer which may be directly applied to a conductive support, such as woven carbon paper or cloth. This electrode may be directly adhered onto an ion exchange membrane. The nanoparticles comprise nanometer-sized transition metals such as cobalt, iron, nickel, ruthenium, chromium, palladium, silver, gold, and copper. In this invention, these catalytic powders substantially replace platinum as a catalyst in fuel cell electrooxidation and electroreduction reactions.