The invention relates to a catalyst, to the use thereof for the electrochemical conversion of methane to methanol and for the direct electrochemical conversion of methane to CO2. The invention also relates to an electrode, in particular for a fuel cell including such a catalyst, as well as to a method for manufacturing such an electrode. The invention further relates to a fuel cell including said catalyst or said electrode. The catalyst according to the invention includes a platinum precursor (II), and optionally a metal-ion precursor M supported by particles of a heteropolyanion (HPA). The invention can be used in particular in the field of the electrochemical oxidation of methane into methanol or CO2.