Copper(I)-bathocuproine complex as carrier in iodide-selective electrode.

Area of Science:

• Electrochemistry
• Analytical Chemistry
• Materials Science

Background:

• Ion-selective electrodes (ISEs) are crucial for monitoring specific ions in various matrices.
• Development of new ionophores is key to enhancing ISE performance, selectivity, and detection limits.
• Copper complexes have shown potential as ionophores in potentiometric sensors.

Purpose of the Study:

• To prepare and characterize a novel PVC membrane electrode for iodide ion detection.
• To evaluate the electrochemical performance of the electrode, including its response range, detection limit, and Nernstian behavior.
• To assess the selectivity, response time, operational pH range, and stability of the iodide-selective electrode.

Main Methods:

• Fabrication of a PVC membrane electrode incorporating Cu(I)-bathocuproine as the ionophore.
• Potentiometric measurements to determine the electrode's response characteristics (linear range, detection limit, slope).
• Selectivity studies using the fixed-interference method to evaluate interference from other anions.
• Testing the electrode's performance across a range of pH values and assessing its operational stability and response time.

Main Results:

• The prepared PVC membrane electrode demonstrated a linear potentiometric response for iodide ions over a wide concentration range (5.0x10⁻⁶ to 2.0x10⁻¹ mol/L).
• The electrode achieved a low detection limit of 1.0x10⁻⁶ mol/L and exhibited Nernstian behavior with a slope of -56.8 mV/decade.
• The iodide-selective electrode showed fast response times (10s), good selectivity against various anions, a stable operational lifetime of at least 3 months, and functionality within a pH range of 3-9.

Conclusions:

• The Cu(I)-bathocuproine based PVC membrane electrode is a highly effective sensor for iodide ion determination.
• The electrode's excellent performance characteristics, including sensitivity, selectivity, and stability, make it suitable for practical applications.
• The developed electrode can be reliably used as an indicator electrode in potentiometric titrations of iodide ions.