Study On Preparation, Property And Application Of Sol-Gel Chemical Modified Iodide Electrode

Sol-Gel technology used to preparing thin-film possess many attractive properties,including high-purity,strong-uniformity,low temperature and reaction condition is easy to control. The process condition is simple. The mixture ratio,aperture and structure can be adjusted. So,Sol-Gel technology has been use in the filed of preparing film research extensively in recent years. It has been an important method for preparing functional thin-film material evoking strong interest. Embedding biological macromolecule and electrical active material to prepare biosensor and chemical modified electrode with Sol-Gel technology has been one of major areas of electro analysis chemistry.This paper has studied embedding electrical active material to prepare iodide electrode with Sol-Gel technology. By the optimized condition of Sol-Gel process,the film has good quality was prepared. The performances of the electrode have been tested in the paper. The effects of solution stability,temperature and interferent have also been studied. Cyclic voltammetry was used to investigate formative process of sensitive film. It prove Sol-Gel film have good effect on embedding AgI. The response mechanics has been discussed in this paper. I- can go into network construction and make stereo response,which help to improve the sensitivity. The effect of some kinds of surfactants is tested. It has been shown that some anion-surface active agent have positive effect on measurement, with dosage of CMC, the respond linear scope is extended obviously,too.The Sol-Gel chemical modified iodide electrode showed Nernst response to I- with a slope of 58.321mV/pI-,and a linear range of 10^-1～10^-7mol/L.The detection limit is 4.6×10^-8mol/L.When concentration of I- is higher than 10^-5mol/L,the response time of electrode is less than 2 minute. Because of excellent performance, the modified electrode can be compared with commodity iodide electrode and have been a new member in the family of chemistry sensor. It had been use for the determination of iodine ion and Vc content in actual sample. The results showed that the method is simple, rapid and of satisfactory precision. The average recovery is 100.6% and 99.5%.