| Ti-based oxide electrodes in electrochemical industry, such as the degradation of pollutant and electrochemical synthesis, are very promising. However, while titanium anodes were used in the case of strong acid electrolyte, the titanium dioxide insulator was formed because of active oxygen of anode, the conductivity and binding of anode were weakened. Addition of oxides solid solution intermediate provides a new method to improve corrosion resistance. The electrocatalytic of electrodes can were discussed quantificationally by fractal dimension and kinetic parameters. Therefore it is important to study electrocatalytic performance and stability of proof acid anode.Ti/SnO2+Sb2O4/PbO2 anode was prepared by means of the thermal decomposition and electrodeposition technology. The surface morphology and microstructure of the coating were characterized by means of SEM. The cyclic voltammetry and kinetics parameters were measured by three electrodes system in acid solution under different scanning speed. The fractal geometry theory was introduced into titanium based oxide electrode system, the correlation between surface fractal dimension of the oxide electrode and the electrocatalytic performance has been discussed. The fractal dimensions of electrode surface were quantificationally calculated under the different Sb doping concentration simultaneously based on the correlation between different scan rate and peak current, the relation between fractal dimension and electrocatalytic performance of evolution oxygen in acid solution was discussed emphatically. Conductivity of electrode was investigated by AC impedance experiment. The anticipated service life of the oxide anodes were inspected by accelerated life method in 1.0mol/L H2SO4 solution at 4A-cm-2. The conclusions are as follows:1. The surface of the SnO2+Sb2O4 electrode have the crystal structure, can form a good solid solution which can effectively prevent oxygenated species transport toward the titanium substrate. The activated layer of the Ti/SnO2+Sb2O4/PbO2 anode with a high surface area and a shape of mushroom have a good electrocatalytic performance.2. The obtained results from the cyclic voltammetry measurements showed that the Ti/SnO2+Sb2O4/PbO2 anode surface had a complex fractal structure with a high value of fractal dimension, when the doping ratio is 2% and 10%, the electrocatalytic performance of evolution oxygen is better.3. Accord to the experiment of AC impedance, Rfis 2.737Ω·cm2, the result show that the conductivity of electrode reached a maximum when the doping ratio is 6%.4. Experiment of accelerated life show that anticipated service life of Ti/SnO2+Sb2O4 electrode is up to 28.75 h when its sintering temperature is 450℃, and doping ratio is 6%.The anticipated service life of Ti/SnO2+Sb2O4/PbO2 anode is up to 88.5 h when the doping ratio is 6%.In this paper, the fractal geometry theory was introduced into titanium based oxide electrode system, the fractal dimensions of electrode surface were quantificationally calculated, and the correlation between surface fractal dimension and the electrocatalytic performance was discussed. This provides a new idea for the study of electrocatalyst.
|
PDF Full Text Request