Electroanalytical properties of metal–oxide electrodes formed by plasma electrolytic oxidation

Ti/TiO2 and Ti/TiO2/Pt electrodes were prepared using the method of plasma electrolytic oxidation (PEO) and applied for potentiometric indication of different types of chemical reactions. The structural features of surface electrodes have been investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and energy-dispersive spectroscopy (EDS) techniques. On the surface of modified Ti/TiO2/Pt electrodes platinum is present in an atomic state in the form of nanoparticles. Ti/TiO2/Pt electrodes showed an excellent performance for end-point indication potentiometric titrations similarly to the traditional Pt electrodes. In addition, this sensor has some good analytical characteristics such as sensitivity, good reproducibility, and simple preparation procedure. As compared with the monolith Pt electrode, the Ti/TiO2/Pt electrode showed several advantages including low cost and high stability.