Electrochemical and SEM characterization of NiTi alloy coated with chitosan by PLD technique

The production of a wide variety of biocompatible thin films by laser ablation deposed on the biomaterial substrates does not induce inflammatory response and repulsion by the immunization human body. Anodic potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques were used for the study of the electrochemical behavior of coated NiTi with chitosan through pulsed laser deposition (PLD) technique. Experiments were carried out using two different electrolytes: physiological 0.9 wt% NaCl solution (PS) and PS + hydrochloric acid (APS) at 37 ± 1 °C. In addition, scanning electron microscopy was employed to observe the surface morphology after maintaining in both electrolytes. The corrosion resistance was evaluated by means of the corrosion and passive corrosion currents. The electrochemical properties of the coated NiTi sample at the open circuit potential at different immersion time in PS and APS were studied by EIS. Equivalent circuits were used to model EIS data, in order to characterize samples' surface.