Preparation and Study of Ti/TiO 2 ,SbO x pH Electrodes

Electrodes of the composition Ti/TiO 2 ,SbO x were obtained by single-stage plasma electrolytic oxidation in aqueous electrolytes with antimony hydroxocomplexes. The surface morphology and composition of TiO 2 ,SbO x layers deposited on titanium were studied by scanning electron microscopy, X-ray diffraction analysis, and X-ray photoelectron spectroscopy. The obtained layers contain anatase TiO 2 and up to 1 at % of antimony as Sb 2 O 3 and Sb 2 O 5 . The resulting Ti/TiO 2 ,SbO x electrodes were tested as pH sensors. They have close to Nernst electrode function in the pH range from 2 to 10 (53 ± 1 mV/pH). In the acid–base titration of strong (HCl) and weak (CH 3 COOH) acids with Ti/TiO 2 ,SbO x electrodes, potential jumps are obtained that are not inferior in magnitude to the potential jump for a glass electrode. A possibility of using Ti/TiO 2 ,SbO x electrodes to determine the alkalinity of technogenic waters is shown.