Cathodic Stripping Voltammetry of Selenium(IV) at a Silver Disk Electrode

Area of Science:

• Analytical Chemistry
• Electrochemistry

Background:

• Accurate determination of selenium(IV) is crucial for environmental and biological monitoring.
• Existing selenium determination methods can be complex or lack sensitivity.

Purpose of the Study:

• To develop a simple, reproducible, and sensitive method for selenium(IV) determination.
• To optimize differential pulse cathodic stripping voltammetry for selenium analysis.

Main Methods:

• Differential pulse cathodic stripping voltammetry (DPCSV) using a rotating silver disk electrode.
• Electrodeposition of selenium(IV) as silver selenide in an acidic medium.
• Cathodic stripping in a sodium hydroxide solution.

Main Results:

• Linear calibration curve for selenium(IV) up to 40 ng mL(-1) with a low relative standard deviation (2.7%).
• Achieved a low detection limit of 0.20 ng mL(-1) (3σ).
• The electrode demonstrated excellent reproducibility over at least 20 uses without polishing.

Conclusions:

• The developed DPCSV method is a significant improvement over existing techniques for selenium(IV) determination.
• The method is simple, reproducible, and highly sensitive, suitable for routine analysis.
• The method shows robustness against potential interferences, including dissolved oxygen.