Preparation and characteristics of ordered porous ZnO films by a electrodeposition method using PS array templates

Ordered porous ZnO films were electrodeposited on an ITO glass substrate covered with PS array templates by using a zinc nitrate aqueous solution as the electrolyte. The electrochemical deposition process was analysed and the characteristics of the porous films were discussed. The results showed that Zn²⁺ had an analogous catalysis to NO⁻₃ during the nucleation-growth process of ZnO, and its concentration had an important effect on the current density, growth rate and the film morphology. Deposition temperature also had a relation with the induction period time and film morphology. The porous film prepared at 0.1 M Zn(NO₃)₂, −1.1 V potential and 70 °C was a hexagonal wurtzite structure. The approximate specific surface area was 2.76 m² g⁻¹. The optical transmittance spectrum gave a relatively high transmittance of 60% beyond 500 nm, and the optical band-gap of the ZnO film was 3.36 eV.