Conductive Polymer Nanoparticles as Solid Contact in Ion-Selective Electrodes Sensitive to Potassium Ions

Area of Science:

• Electrochemistry
• Materials Science
• Analytical Chemistry

Background:

• Development of selective electrodes for ion detection is crucial in various analytical applications.
• Poly(3-octylthiophene-2,5-diyl) (POT) and carbon black (CB) are promising materials for electrochemical transducers.
• Existing methods face challenges in sensitivity, stability, and interference.

Purpose of the Study:

• To propose a novel preparation method for nanocomposites of POT and CB.
• To utilize these nanocomposites as transducers in an all-solid potassium ion selective electrode.
• To characterize the electrochemical properties and performance of the developed electrode.

Main Methods:

• Nanocomposite preparation with POT acting as a dispersant for CB.
• Electrochemical characterization using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and chronopotentiometry.
• Performance evaluation including detection limit, slope, hydrophobicity, and anti-interference tests.

Main Results:

• The POT-CB nanocomposites exhibit high conductivity, capacitance, and stability.
• The potassium ion selective electrode achieved a detection limit of 10^-6.2 M with a slope of 57.6 ± 0.8 mV/decade.
• The electrode demonstrated high hydrophobicity (static contact angle of 139.7°) and resistance to light, O₂, and CO₂ interference.

Conclusions:

• The proposed POT-CB nanocomposite is an effective transducer for all-solid potassium ion selective electrodes.
• The developed electrode offers high sensitivity, stability, and excellent anti-interference properties.
• This advancement holds potential for improved potassium ion monitoring in various fields.