Film growth of TiO₂ by pulsed electrodeposition: Influence of the frequency of the voltage pulses

TiO2TiO2films were grown by pulsed electrodeposition on stainless steel substrates, and they were studied the influence of the frequency of the voltage pulse on the amount of mass deposited and the morphology of the samples. The electrolytic cell was added with a system of agitation with a motor of micro sonic vibrations for the elimination of hydrogen bubbles produced during the growth. The voltage pulses were of - 2500 mV in the cathodic zone and -500 mV in the anodic zone; the frequency of the pulses was between 0 and 1 Hz. After their growth the films were dehydrated at 120°C by one hour; and annealed at 450 °C by 2 hours. The structural and morphologic properties were studied by means of X ray Diffraction and Scanning Electron Microscopy. The results show that the agitation of the solution helps stabilizing/maintaining the current during the growth. The films had an amorphous structure after the dehydration, acquiring the anatasa crystalline structure after thermal annealing. The deposited mass and the morphology depend on the frequency of the applied voltage pulses during the growth.