Electrochemical behavior of stannum at chitosan and multi-wall carbon nanotubes modified glassy carbon electrode and its determination
QI Tong-xi1, QI Lei2
1. School of Chemical Engineering, Shandong University of Technology, Zibo 255049, China;2. College of Chemistry and Chemical Engineering, Jinan University, Jinan 250022, China
Abstract： The chitosan and multi-wall carbon nanotubes modified glass carbon electrode (CTS-MWCNT-GC) was successfully prepared. The electrochemical behavior of stannum at CTS-MWCNT-GC and the corresponding reaction mechanism of electrode were investigated by differential pulse stripping voltammetry. A new method for the determination of trace stannum was described by optimizing the determination conditions. It was found that in 1.0 mol/L HCl solution , stannum was accumulated on the surface of the modified electrode at -1 000 mV. When scanning linearly was from -1 000 mV to 0.00 mV at a scan rate of 800 mV/s, a sensitive stripping peak of stannum appeared at -630 mV. The peak current showed good linearity with the concentration of stannum in the range of 4.2×10-8-1.3×10-5 mol/L. Detection limit was 3.1×10-9 mol/L. This method has been applied to the determination of tracing stannum in pig iron and alloy steel samples, and the results were consistent with those obtained by FAAS.
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