Reparation and Electrochemical Performance of Acetylene Black-Doped Ti-PbO2 Electrode with High Electron Transfer Rate

Abstract

During the electrochemical preparation process, the electron transport rate in the PbO2 active layer could be greatly increased resulting from reduction in the oxidation of the Ti substrate, which effectively improved the service life and catalytic degradation efficiency of the PbO2 Dimension Stable Anode (PbO2 DSA) electrode. Through adding nano-acetylene black (ACET) and polyvinyl pyrrolidone (PVP) into the plating solution, an ACET doped Ti/PbO2 electrode was successfully prepared via an anodic oxidation method. Results of field emission scanning electron microscope (FESEM), diffraction of X-rays (XRD), transmission Electron Microscope(TEM) and X-ray photoelectron spectroscopy (XPS) characterization indicated that 2.10 ∼ 2.75 wt% of ACET doping amount hardly changed the morphology and lattice constant of the PbO2 electrode. With electrochemical alternating current impedance spectroscopy (EIS) and cyclic voltammetry (CV), it confirmed that ACET reduced the charge transfer impedance (Rct) of the PbO2 electrode up to 95%, and restrained the potential of oxygen evolution reaction(OER). With the increase of electron transport rate, the generation rate of hydroxyl radicals (·OH) on the electrode surface was enhanced significantly. Compared with the Ti/PbO2 electrode, the ACET-doped Ti/PbO2 electrode exhibited higher electrocatalytic efficiency to phenol degradation. During the degradation process, the consumption of time and energy could be reduced by 33% and 34%, respectively. At the same current density, the required voltage for preparing the ACET-modified Ti/PbO2 electrode was much lower. In the assistant of lower deposition voltage, the ACET-doped Ti/PbO2 electrode possessed a stronger binding force to Ti substrate, and meanwhile obtained a longer lifespan.