| The nanometer-sized Ti/SnO2-Sb2O4 electrode has been prepared by a sol-gel dip-coating technique using inorganic salts (SnCl2 2H2O,SbCl3) as the precursor, and surface morphology and microstructure of the coating were examined by means of XRD and TEM, According to the XRD patterns of the samples, the peak positions in each sample agree well with the reflections of bulk SnO2 (rutile), and the average crystallite sizes (D) determined from (110)crystalline plane are in nanometer scale and grow slowly with the increase of heat treatment temperature. The particle size is about 6.5nm. On the other hand, there is no apparent change in the average crystallite sizes (D) with Sb doping. The TEM images show that the average crystallite sizes are increased with the increase of heat treatment temperature, after the addition of Sb, theSnC>2 particles are distributed equably and the diameter is diminished. The particle size of pure SnO2 is about 16.2nm, however, the particle size of SnO2 with Sb is only 6-7nm, which is in accord with the results in XRD.Ti-based tin oxide electrodes are of widespread interest in many fields such as treatment of wastewater, organic electrical synthesize and chlorine- alkali industry etc, especially treatment of industrial wastewater because of their unique properties, these include: high over potential for oxygen-evolution, good electrical conductivity and catalytic property. In order to study the effect of SbCl3 adding amount and sintering temperature on the properties of electrodes, the electrodes used in different electrolytes (H2SO4, Fe(CN)6]3-/[Fe(CN)6]4-, wastewater contained with phenol) were tested by the cyclic voltammetry. The results indicate that the electrode appeared the best performance when the Sb is 4% in sol-gel solution and the sintering temperature is 600℃. The over potential of oxygen evolution at electrode with the best performance in lmol L-1 H2SO4 electrolyte is higher (2.1182v )at current density lOmA cm-2, and exchanged current density i0 is 2.42x10-3A#cm"2,and the accelerated lifetime of electrode at strong current density is 25h, and fractal dimensions of electrode is 1.8514.The electrode with the best performance was used for treatment of phenol in wastewater, conversion rate of phenol is 96.5% and current efficiency is 73.5%; Compared with Ti/SnO2and Ti/PbO2 electrodes, the results show that economization on electricity is 32.7% to Ti/SnO2 electrode and 62.7% to Ti/PbO2 electrode.
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