It is shown that pure Co3O4 and MnCo2O4 films can be prepared at 150 degrees C by spray pyrolysis of the metal nitrate aqueous solutions, provided that the flow rate and concentrations are lowered and optimized in comparison with classical procedures, and that undecomposed nitrates are further eliminated by prolonged washing. High roughness factors are obtained, yielding electrodes with a higher activity for the oxygen evolution reaction than electrodes prepared by conventional spray pyrolysis at higher temperatures.