An air-breathing electrode was fabricated using a catalyst combination of nickel nano-powder and molybdophosphoric acid (H 3 PMo 12 O 40 ) immobilised in a Nafion® based ink. The first investigation of the use of H 3 PMo 12 O 40 , a heteropolyacid (HPA), as an oxygen evolution catalyst and its application in an alkaline media is presented. Incorporating molybdophosphoric acid with nickel nano-powder resulted in more than a 650mV reduction in potential difference between the oxygen evolution and reduction reactions at a current density of 44mAcm −2 when compared with electrodes made with the nickel nanopowder alone. The electrodes showed good stability and are potentially suitable for applications such as water electrolysis, unitised fuel cells and secondary metal–air batteries.