Hierarchical ZnxCo3‐xO4 Nanoarrays with High Activity for Electrocatalytic Oxygen Evolution.

ZnxCo3-xO4 nanoarrays are grown hydrothermally on Ti foils using appropriate ratios of Zn(NO3)2 and Co(NO3)2, NH4F and Co(NH2)2 in H2O together with the Ti substrate (autoclave, 120 °C, 10 h).