NOVELTY - Manufacturing an electrocatalyst comprising a porous carbon support material, catalytic material and macrocyclic compounds, comprises: (i) providing a template acting as pore structure directing agent during formation of a highly porous electrically conducting templated carbon substrate; (ii) mixing the template with precursor substances of the catalytic material, macrocyclic compounds and carbon; and (iii) exposing the mixture of template and the precursor substances to a carbonization process during which the precursors react and transform mixture into carbonized template composite.    USE - The method is useful for manufacturing electrocatalyst, which is useful in electrochemical reactions, and for manufacturing MEA with gas diffusion layers suitable for use in fuel cell (all claimed) for transportation and power generation.    ADVANTAGE - The electrocatalyst improves the performance and oxygen reduction efficiency at the cathode in non-platinum electrochemical fuel cells, and exhibits high conversion rates for electrocatalytic oxygen reduction and low conversion rates for fuel oxidation as well as low sensitivity to poisoning by the fuel when operated in electrochemical fuel cells.    DETAILED DESCRIPTION - Manufacturing an electrocatalyst comprising a porous carbon support material, a catalytic material in the form of at least one type of metal, and macrocyclic compounds chemically bound to the carbon support and capable of forming complexes with single metal ions of the metal or metals, comprises: (i) providing a template capable of acting as pore structure directing agent during formation of a highly porous electrically conducting templated carbon substrate; (ii) mixing the template with precursor substances of the catalytic material, macrocyclic compounds and carbon; and (iii) exposing the mixture of the template and the precursor substances to a carbonization process during which the precursors react and transform the mixture into a carbonized template composite in which the carbon part of the composite is chemically bound to macrocyclic compounds present in complexes with the metal. INDEPENDENT CLAIMS are also included for:    (1) electrocatalyst for electrochemical reactions comprising the porous electrically conducting carbon substrate, the catalytic material, and the macrocyclic compounds comprising carbon atoms and nitrogen, sulfur, oxygen, silicon, boron or phosphorus capable of forming complexes with single metal ions of the metal or metals used as catalytic material, where the metal containing macrocyclic complexes are incorporated into and integrated with the carbon substrate material, and the nitrogen, sulfur, oxygen, silicon, boron or phosphorus form bonds on the one hand to the metal ion and on the other hand to the carbon substrate;    (2) manufacturing a membrane electrode assembly (MEA) with gas diffusion layers (GDL's) suitable for use in fuel cell, comprising: mixing the electrocatalyst material with an ionomer in the presence of a solvent e.g. lower aliphatic alcohols and if beneficial including water to prepare an ink, and depositing the ink mixture thus obtained on to an ionomer membrane or onto a gas diffusion layer, and sandwiching the ink mixture between the membrane and the gas diffusion layer, where the latter acts to provide gaseous reactants to the electrode and acts as current collector, and sandwiching the obtained sandwich structure with a second electrode with GDL on the other side of the membrane, thus obtaining a MEA with GDL's for use in a fuel cell setup; and    (3) fuel cell having first and second electrodes, where at least one of the electrodes comprise the electrocatalyst.