An all-solid-state NO3- ion-selective electrode with gold nanoparticles solid contact layer and molecularly imprinted...

Area of Science:

• Electrochemistry
• Materials Science
• Analytical Chemistry

Background:

• Single-layer electrodes suffer from poor conductivity and water layer interference.
• Existing ion selective electrodes require improvements for practical applications.

Purpose of the Study:

• To develop a double-layer all-solid-state ion selective electrode overcoming limitations of single-layer designs.
• To enhance nitrate detection in water and liquid fertilizer using advanced materials.

Main Methods:

• Fabrication of a double-layer electrode with a gold nanoparticles solid contact layer and a nitrate-doped polypyrrole molecularly imprinted polymer membrane via electrodeposition.
• Optimization of electrodeposition parameters for both layers.
• Electrochemical performance testing, including potentiometric water layer analysis and contact angle measurements.

Main Results:

• The developed electrode demonstrated a Nernstian response (-50.4 mV/decade) and a low detection limit (5.25×10-5 mol/L).
• The gold nanoparticles solid contact layer exhibited excellent hydrophobicity (contact angle 112.35°), preventing water film formation.
• The electrode showed fast response, superior potential stability, and a long operational lifetime.

Conclusions:

• The double-layer electrode design effectively addresses conductivity and water layer interference issues.
• This novel electrode is highly suitable for accurate and reliable nitrate detection in environmental and agricultural samples.
• The use of nanomaterials and conductive polymers represents a significant advancement in ion selective electrode technology.