(Invited) Conventional and Innovative Electrocatalysts for PEM Water Electrolysis

In conventional polymer electrolyte membrane (PEM) water electrolysis cells, platinum particles are used at the cathode for the hydrogen evolution reaction (HER) and iridium oxide particles at the anode for the oxygen evolution reaction (OER). Although noble metal contents are small, the large scale deployment of PEM technology for power-to-gas applications is calling for cheaper materials. Molecular organo-metallic complexes containing transition metals as active centers offer some promising alternative. Examples with cobalt and iron clathrochelates used for the HER are reported in this communication.