Abstract ZnO nanomaterials (ZnO T , ZnO S and ZnO P ) were successfully synthesized by thermal decomposition, sol–gel auto combustion and precipitation methods, respectively. Co 3 O 4 /ZnO catalysts were synthesized by impregnation method, nominated as CoZnO T , CoZnO S and CoZnO P, respectively. The as-prepared catalysts were characterized by XRD, N 2 adsorption–desorption isotherms, HR-TEM and FT-IR techniques. The S BET of CoZnO nanomaterials were significantly higher than those of the pure oxides. Further, the Co 3 O 4 /ZnO sample in which ZnO synthesized via sol–gel combustion using citric acid (CoZnO SCI ) showed the largest surface area while CoZnO P sample showed the smallest value. The HR-TEM images showed that addition of Co 3 O 4 to ZnO catalyst and the calcination temperature affected the morphology. The catalytic decomposition of H 2 O 2 of the Co 3 O 4 /ZnO catalysts is higher than that of the pure oxides. The most catalytically active sample is Co 3 O 4 /ZnO in which ZnO synthesized via thermal decomposition of zinc carbonate (CoZnO TC ) while CoZnO SCI catalyst being the less active one.