NOVELTY - The fuel cell comprises an ion exchange membrane positioned between first and second porous catalytic layers (20, 22) and first and second electrodes (16, 18). Each of the catalytic layers comprises a carbon-free non-noble porous metal nanostructured substrate, and a coating layer comprising a noble metal. The nanostructure comprises nanoparticles, nanowires, honeycombs and inverse opals. The first electrode is an oxygen or air cathode. The second electrode is a hydrogen anode and a methanol anode. A platinum loading in the catalyst layers is 0.1-0.04 mg/cm2.    USE - The fuel cell such as polymer electrolyte fuel cell, hydrogen-air fuel cell and direct methanol fuel cell is useful as power sources for automotive, stationary and portable applications such as military radio stations and laptop computers.    ADVANTAGE - The fuel cell is easy to fabricate, and has high power and energy output, good power density and performance, long lifetime, high flexibility and superior mass-transfer properties, and increases the back pressure and the flow rates of the electrode assembly thus measuring the intrinsic performance of the thick layers.    DETAILED DESCRIPTION - The fuel cell comprises an ion exchange membrane positioned between first and second porous catalytic layers (20, 22) and first and second electrodes (16, 18). Each of the catalytic layers comprises a carbon-free non-noble porous metal nanostructured substrate, and a coating layer comprising a noble metal. The nanostructure comprises nanoparticles, nanowires, honeycombs and inverse opals. The first electrode is an oxygen or air cathode. The second electrode is a hydrogen anode and a methanol anode. A platinum loading in the catalyst layers is 0.1-0.04 mg/cm2. The nanoporous catalytic layer has a thickness of 0.1-10 mu m. The nanostructure has a pore diameter of 5-50 nm. The ion exchange membrane comprises a proton-conducting polymer, and fills a part of the pores of the substrate. The non-noble metal comprises a first-row transition element, valve metal and/or coinage metal. The fuel cell has an energy output of 0.02 g Pt/kW. INDEPENDENT CLAIMS are included for:    (1) a membrane-electrode assembly; and    (2) a method for preparing a fuel cell.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic view of a single stack hydrogen-air fuel cell.    Membrane-electrode assembly (12)    Ion conducting layer (14)    Electrodes (16, 18)    Catalytic layers (20, 22)    Gas diffusion layers. (24, 26)