A method of forming an electrode having an electrochemical catalyst layer is disclosed, which comprises providing a substrate with a conductive layer formed on the surface of a substrate, conditioning the surface of the substrate, immersing the substrate in a solution containing polymer-capped noble metal nanoclusters dispersed therein to form a polymer-protected electrochemical catalyst layer on the conditioned surface of the substrate, and thermally treating the polymer-protected electrochemical catalyst layer at a temperature approximately below 300° C.