A process for making a catalytic electrode containing a transition metal nano-catalyst without using spray or thermal decomposition, and a process for making an electrochemical cell with a catalytic electrode. The nano-catalyst is a particulate material that includes particles that are at least partially oxidized, preferably to include at least oxide shells, before mixing with an activated carbon and binder in a liquid medium to adhere particles of the nano-catalyst to internal and external surfaces of the particles of activated carbon. Oxidation of the nano-catalyst particles allows the mixing of the nano-catalyst, activated carbon and binder in air rather than an inert gas atmosphere and can avoid the use of potentially dangerous liquid media such as highly volatile alcohols.