The invention discloses a preparation method of a platiniridium / carbon-
electro catalyst by using
microwave synthesis. The preparation method comprises the following steps of: evenly distributing nanometer carbon carriers in
ethylene glycol solution containing both
platinum metal salt and
iridium metal salt at the same time, wherein the concentration of the
platinum salt and the
iridium salt is 0.001 to 0.01 mol / L; adding
sodium acetate as a stabilizer, wherein the concentration of the
sodium acetate in the resulting solution is 0.005 to 0.03 mol / L; then heating the well-distributed mixture of the nanometer carbon carriers and the
metal salt
ethylene glycol solution for 2 to 4 minutes by
microwave radiation, and then filtering, washing and
drying to obtain the platiniridium / carbon-electro catalysts. The
atomic composition ratio of a
platinum iridium alloy is PtxIry, wherein x is 0.1 to 1, and y is 0.1 to 1. The invention has the advantages that the nano-particles of the
platinum iridium alloy, which are loaded on the surfaces of the carbon carriers, have small grain
diameter averagely from 3 to 4 nm, and the grain
diameter distribution is narrow, and the loading capacity of the
alloy nano particles on the surface of the carbon carrier is 5% to 30%. The invention also has the advantages of high speed, simple process, high efficiency and energy saving. The platiniridium / carbon-
electro catalyst is widely used in the field of
electrochemical energy conversion.