The Principle of Detect SO2 Concentration by Using the Electrochemical Method in Ionic Liquid
HUANG Qing1,2, HU Yang3, WANG Jiakai 4, JIANG Kai5, WU Tian1,2†1. College of Chemistry and Life Science, Hubei University of Education, Wuhan 430205, Hubei, China; 2. Institute of Materials Research and Engineering (IMRE), Hubei University of Education, Wuhan 430205, Hubei, China; 3. College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, China; 4. School of Materials Science and Engineering, Hubei University, Wuhan 430062, Hubei, China; 5. School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China
The reduction of SO2 with different concentrations at a platinum microelectrode was investigated by cyclic voltammetry (CV) in 1-(butyl)-3-methylimidazolium hexafluorophosphate ([Bmim]PF6). We speculated that the reaction mechanism of reduction may form a macromolecular complex, and the higher the concentration of SO2, the larger the molecular weight of the complex. The higher the concentration of SO2, the greater the diffusion coefficient of SO2 in [Bmim]PF6. There is a good quadratic function relationship between the reduction peak current and SO2 concentrations in the range from 2% to 100%, which promises a kind of ionic liquid electrolyte for the detection of SO2 gas with a wide range of concentrations.
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