Anodized graphite as an advanced substrate for electrodeposition of PbO2. (June 2022)

• Record Type: Journal Article
• Authors: Abedini, Amin; Ebrahimi Valmoozi, Ali Asghar; Seyyed Afghahi, Seyyed Salman
• Is Part Of: Materials today communications. Volume 31(2022)
• Publication Date: 2022-06
• Subjects: Lead dioxide -- Electrodeposition -- Anodization -- Graphite -- Substrate; Materials science -- Periodicals; 620.11
• DOI: 10.1016/j.mtcomm.2022.103464
• Languages: English
• ISSNs: 2352-4928

Abstract

Abstract: Graphite plate has been employed as a crucial substrate for electrodeposition of PbO2 to increase charge transfer and electronic conductivity. This work is evaluated the effect of electrochemical pretreatment (anodization in alkaline, acidic, and buffer solution) on graphite substrate to be reported as an advanced substrate for PbO2 electrodeposition. The morphological features and electrochemical performance are analyzed by using field emission scanning electron microscopy (FESEM), Atomic Force Microscopy (AFM), X-Ray diffraction (XRD), chronopotentiometry, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), Linear sweep voltammetry (LSV) and Tafel plot. The results are indicated that the roughness, porosity, and capacitance are increased after the anodization. Also, the charge transfer resistance is decreased for oxygen evolution reactions on the graphite surface. Although alkaline anodization is provided the lowest electrical capacitance, it is created the highest charge transfer resistance in comparison to acidic and buffer anodization. The deposition of PbO2 on the alkaline anodized graphite substrate is formed the porous PbO2 architecture with small particle sizes and the highest current efficiency. It also is shown the lowest ohmic resistance (0.48 ohm) and charge transfer resistance (2.44 ohm). Therefore, the result can be drawn that the electrochemical activity of PbO2 coated on BG could be enhanced by the alkaline anodization of graphite substrate. Graphical Abstract: ga1 Highlights: Anodization of graphite in alkaline, acidic and buffer solution as pretreatment. Increasing capacitance and OER activity after the acidic anodization of graphite. Improving porosity and strength of PbO2 coating by alkaline anodization of graphite. Promotion of electrochemical activity of PbO2 by alkaline anodization of graphite.