TY - JOUR AU - Tot, Pham Thi AU - Thuy, Mai Thi Thanh AU - Binh, Phan Thi PY - 2022/08/31 Y2 - 2024/03/28 TI - Electrochemical characterization of PbO2-TiO2 composite prepared on stainless steel substrate by cyclic voltammetry method JF - Vietnam Journal of Science and Technology JA - Vietnam J. Sci. Technol. VL - 60 IS - 4 SE - Materials DO - 10.15625/2525-2518/16966 UR - https://vjst.net/index.php/jst/article/view/16966 SP - 631640 AB - <p>In this study, PbO<sub>2</sub>-TiO<sub>2</sub> composite was prepared on stainless steel (SS) substrate by cyclic voltammetry (CV) method from mixed solution containing TiO<sub>2</sub> sol-gel with size from 10 to 50 nm. In the electrochemical deposition, TiO<sub>2</sub> nanoparticle will disperse in the growing PbO<sub>2</sub> coating to create PbO<sub>2</sub>-TiO<sub>2</sub> composite. These TiO<sub>2</sub> nanoparticles are delivered from the electrolyte bulk to the eletrode surface by diffusion and migration.The electrochemical properties of SS/PbO<sub>2</sub>-TiO<sub>2</sub> electrodes were investigated in 0.5 M H<sub>2</sub>SO<sub>4</sub> solution by CV, PP (potentiodynamic polarization), and EIS (electrochemical impedance spectroscopy) methods with and without UV irradiation. The results showed that the exchange current density (i<sub>o</sub>), the value o (i<sub>p,a</sub> and i<sub>p,c</sub>, respectively) depended on the TiO<sub>2</sub> concentration. With a solution containing  2 g/L TiO<sub>2</sub>, the value of the redox peaks is the largest and the exchange current density obtained is close the maximum value, indicating that the SS/PbO<sub>2</sub>-TiO<sub>2</sub> composite electrode exhibits the best electrochemical activity under this solution condition. Due to the presence of TiO<sub>2</sub> in the composite, the height of the redox peaks and the exchange current density increased sharply under UV light. This demonstrated that the photo-electrochemical activity of the composite is very good, which  can be used  to remove  dyes in wastewater by electrocatalytic oxidation.</p> ER -