Haibo Lin

Performance characterization of Ti substrate lead dioxide electrode with different solid solution interlayers

In this study, Ti substrate was coated by three different mixed oxides (SnO2–Sb2O5, RuO2–TiO2, IrO2–Ta2O5), then PbO2 was electrodeposited on them to prepare PbO2 electrode. The microstructure of the solid solution interlayers and PbO2 coatings was characterized by scanning electronic microscopy and X-ray diffraction. The results indicated that the above oxides interlayer exited in the form of solid solution and the interlayer covered the Ti substrate largely. Accelerated life test proved that the presence of solid solution interlayer can increase the stability of PbO2 electrodes in electrolysis. Cyclic voltammogram indicated that the PbO2 electrode with the solid solution interlayer have more active surface area in sulfuric acid solution. Linear scanning voltammograms showed that the over potentials of the oxygen evolution are decreased with the addition of the solid solution interlayer. Electrochemical impedance spectroscopy showed that the presence of interlayer can increase the electrochemical activity of oxygen evolution reaction and electrical conductivity.

Anodic preparation and supercapacitive performance of nano-Co3O4/MnO2 composites

Nano-Co3O4/MnO2 composites have been prepared by anodic composite deposition from Mn(NO3)2 solutions containing different amounts of suspended Co3O4 particles. Chemical composition, crystal structure and surface morphology of the composites were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The kinetics of the formation of nano-Co3O4/MnO2 composites was investigated via analyzing potential–time curves. The supercapacitive performance of the composites was examined by cyclic voltammetry (CV), galvanostatic charge–discharge (GCD) and electrochemical impedance spectroscopy (EIS). Intrinsic relations between surface structure and supercapacitive performance were discussed based on voltammetric charge analysis. When the Co3O4 volume fraction in the composite was 0.23, the specific capacitance of the composite reached 317 F g−1 at a scan rate of 5 mV s−1, increased by about 37% compared with pure MnO2. This composite also showed enhanced power performance. Furthermore, it exhibited excellent cycling stability and the specific capacitance retention was 93.4% after 5000 charge–discharge cycles, while the retention for pure MnO2 was 79.6%.

Feasibility and advantage of biofilm-electrode reactor for phenol degradation

The new biofilm-electrode method was used for the phenol degradation, because of its low current requirement. The biofilm-electrode reactor consisted of immobilized degrading bacteria on Ti electrode as cathode and Ti/PbO2 electrode as anode. With the biofilm-electrode reactor in a divided electrolytic cell, the phenol degradation rate could achieve 100% at 18 h which was higher than using traditional methods, such as biological or electrochemical methods. Chemical oxygen demand (COD) removal rate of the biofilm-electrode reactor was also greater than that using biological and electrochemical method, and could reach 80% at 16 h. The results suggested that the biofilm-electrode reactor system can be used to treat wastewater with phenol.