Fabrication and Electrochemical Treatment Application of A Novel Lead Dioxide Anode with Superhydrophobic Surfaces, High Oxygen Evolution Potential, and Oxidation Capability

Abstract

A novel PbO(2) electrode with a high oxygen evolution potential (OEP) and excellent electrochemical oxidation performance is prepared to improve the traditional PbO(2) electrode, which is modified by changing the microstructure and wetting ability. A middle layer of TiO(2) nanotubes (NTs) with a large surface area is introduced on Ti substrate, and a small amount of Cu is predeposited at the bottom of TiO(2)-NTs. The modification will improve the electrochemical performance by enhancing the loading capacity of PbO(2) and the combination between PbO(2) and Ti substrate. The hydrophilic surface becomes highly hydrophobic by adding fluorine resin. The improved PbO(2) electrode exhibits a similar morphology, surface wetting ability, high OEP, and electrochemical performance with boron-doped diamond film (BDD) electrode. However, the physical resistance of the PbO(2) electrode is much lower than that of BDD, exhibiting higher conductivity. The hydroxyl radical utilization is significantly enhanced, resulting in a higher oxidation rate and higher removal for 2,4-dichlorophenoxyacetic acid.

Fabrication and Characterization of a PbO2-TiN Composite Electrode by Co-Deposition Method

“…Thus, several efforts have been devoted to further improve its performance in the electrochemical oxidation capability and stability, including inserting the middle layer, 17 doping with elements (Bi, 18 Co, 19 Fe, 20 F, 21 Ce, 22 Cu, 23 etc. ), compounds (TiO 2 , 24 fluorine resin (FR), 25 etc.) or nanocomposites (ZrO 2 nano-particles, [26][27][28] Co 3 O 4 nano-particles, 29 WO 3 nano-particles, 30 CeO 2 nano-particles, 31 etc.).…”

Formation and growth of PbO2 inside TiO2 nanotubes for environmental applications

“…The authors used a nanotubular TiO 2 structure as an anchor for the PbO 2 deposit to form an electroactive layer of PbO 2 with better adherence and mechanical stability, consequently increasing by 3.5 times their life span with respect to Ti/PbO 2 anodes. Although these results are very promising in the direction of developing improved PbO 2 anodes, we suggest that the photoactivity of the TiO 2 NT array is meaningless due to the large amount of PbO 2 deposited into and on the TiO 2 NTs (950.1 g m −2 [63]), leading to a PbO 2 film whose thickness could probably be of several m (Fig. 1b in [63]).…”

“…Although these results are very promising in the direction of developing improved PbO 2 anodes, we suggest that the photoactivity of the TiO 2 NT array is meaningless due to the large amount of PbO 2 deposited into and on the TiO 2 NTs (950.1 g m −2 [63]), leading to a PbO 2 film whose thickness could probably be of several m (Fig. 1b in [63]). If the interest is to develop an electrode material able to exhibit both electro (EC)-and photoelectro (PEC)-catalytic properties, then both TiO 2 and PbO 2 active sites must be exposed on the surface in contact with the electrolyte solution.…”

“…Since the one-dimensional structure of the TiO 2 NT array reduces charge recombination, these interfacial nanostructured layers can be used as a matrix of enhanced photocatalytic activity [52][53][54] or as a support for other materials with surface activity, such as bandgap modifiers and electrocatalysts [55][56][57][58][59][60][61][62]. Such is the case of the electrochemical deposit of PbO 2 on TiO 2 NTs recently reported by Zhao et al [63,64]. The authors used a nanotubular TiO 2 structure as an anchor for the PbO 2 deposit to form an electroactive layer of PbO 2 with better adherence and mechanical stability, consequently increasing by 3.5 times their life span with respect to Ti/PbO 2 anodes.…”

Anodic Materials with High Energy Efficiency for Electrochemical Oxidation of Toxic Organics in Waste Water

“…Thus people also utilized this composites technology to prepare lead dioxide anode. PTFE and polypyrrole have good hydrophobic property and they are applied to introduce hydrophobicity and assist the gases release, aid the interaction between the organic molecules and electrode surface (Hwang & Lee, 1996;Ho & Hwang, 1994;Tong et al, 2008;Yoshiyama et al, 1994;Zhao et al, 2010). The PTFE and polypyrrole may also have the function of reducing the coating films inside stress thus to improve the electrode stability.…”