Annealed Zn-TiO2 nanocomposites electrodeposited: Effect of the substrate

► Zn-TiO2 is prepared by electrodeposition onto titanium and steel substrates. ► The Zn metallic matrix is formed by staked hexagonal plates. ► After the annealing treatment occurs the matrix modification from Zn to ZnO. ► ZnO hollow structures, porous flaky nanosheets and needled grains have grown. ► Schematic representation of the ZnO structures growth' mechanism is proposed.