硫代硫酸盐在铂电极上的电化学氧化行为

he electrochemical oxidation of thiosulfate was investigated by changing the pH and the scan rate. When the pH value is 5 or 6, the cyclic voltammograms show three oxidation peaks at about 0.05V, 0.58V, and 1.02V. With increasing pH value and decreasing the scan rate, the first oxidation peak becomes vary clearly at about 0.05V. Moreover the potential and the current of peaks have linear relationship with the logarithm and the square root of scan rates, respectively. When the pH value is 8~9, there are three obvious oxidation peaks at about 0.05V, 0.91V and 1.22V. The curves of cyclic voltammogram are crossed when the scan rate is under 0.01V/s, and the system exhibits obvious electrochemical oscillations. But when the pH is over 10, the third oxidation peak disappears. Those results indicate the electrochemical oxidation of thiosulfate is very complicated. the mechanism of electrochemical oxidation of thiosulfate has the close relation with the pH of the system.