TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Composition: In the electrode catalyst: the WC/C composite support is present at 60-95 wt.%; and the catalyst component is present at 5-40 wt.%. Preferred Components: The WC/C composite support: has a structure in which tungsten carbide crystalline particles form an island phase, and carbon forms a sea phase around the tungsten carbide crystalline particles; comprise mesoporous particles having an average particle size of 0.01-100 mu m; many pores having a diameter of 2-5 nm; and pore volume of 0.08-0.25 cm3/g. The weight ratio of: palladium to the metal catalyst including gold, iron and/or silver is 40:60-70:30; and palladium to nickel is 99.9:0.1-99.999:0.001. Preferred Method: In the method: the amount of the first mixed solvent used in the preparation of the electrode catalyst is 50-200 parts by weight based on 100 parts by weight of the WC/C composite support, and a mixing ratio of the polyol to the polar solvent in the first mixed solvent is 60-100 parts by weight of the polar solvent based on 100 parts by weight of the polyol; the amount of the metal catalyst precursor used in the catalyst preparation is 3-15 parts by weight based on 100 parts by weight of the water single solvent or the second mixed solvent, and a mixing ratio of the water and the polar solvent in the second mixed solvent is 10-30 parts by weight of the polar solvent based on 100 parts by weight of the water; and the amounts of the palladium precursor and the metal catalyst precursor are adjusted so that a resultant atomic ratio in the electrode catalyst of the palladium to the metal catalyst is 3:3-3:1. EXAMPLE - Cetyl trimethyl ammonium bromide (27 ml, 25%) (CTABr) aqueous solution was prepared as a surfactant-A first dispersion obtained by dispersing ammonium metatungstate (5 g) in water (20 ml), a mixture of resorcinol (1.2 g) and formaldehyde (1.8 ml, 30%) was added to the first dispersion and stirred to obtain a second dispersion. The CTABr aqueous solution and the second dispersion were put into a high-pressure reactor and hydrothermally processed for 2 days at a pressure of 5 atm at 150 degrees C, after the reaction, a tungsten precursor-polymer composite in a gel phase was precipitated on the bottom of the high-pressure reactor, filtered, washed, and then dried for one day at 110 degrees C to obtain dried tungsten precursor polymer composite (11 g). The tungsten precursor polymer composite support (0.6 g), ethylene glycol (101 ml) and distilled water (34 ml) were put into a flask purged with nitrogen gas and stirred. Then a catalyst component precursor aqueous solution obtained by uniformly mixing distilled water (64 ml), palladium chloride (0.25 g), and nickel chloride hexahydrate (0.335 g) was added to the flask. The resultant mixture was stirred for 30 minutes at 25 degrees C and at a pressure of 1 atm. The temperature of the flask was increased to 140 degrees C, and then the resultant mixture was refluxed for 2 hours. The reaction product was filtered, washed, and dried to obtain of palladium-nickel-tungsten carbide and carbon (Pd3Ni3/WC/C) composite support catalyst (0.66 g). In the Pd3Ni3/WC/C composite support catalyst, a weight ratio of palladium to nickel was 99.9:0.1 and the supported amount of palladium was about 18.05 wt.% based on the total amount of the Pd3Ni3/WC/C composite support catalyst.