Nitrate-selective membrane electrode based on bis(2-hydroxyanil)acetylacetone lead(II) neutral carrier

Area of Science:

• Electrochemistry
• Analytical Chemistry
• Materials Science

Background:

• Nitrate ion detection is crucial for environmental monitoring and water quality assessment.
• Development of selective and sensitive electrodes is essential for accurate nitrate quantification.
• Existing nitrate-selective electrodes often face challenges with selectivity and response time.

Purpose of the Study:

• To develop a novel nitrate-selective electrode.
• To investigate the potentiometric performance of a new lead(II) complex ionophore.
• To evaluate the electrode's response characteristics and selectivity for nitrate ions.

Main Methods:

• Synthesis of a bis(2-hydroxyanil)acetylacetone lead(II) complex [(haacac)Pb] as an ionophore.
• Fabrication of a membrane electrode using poly(vinyl chloride) (PVC), dibutyl phthalate (DBP), methyltrioctylammonium chloride (MTOAC), and the ionophore.
• Potentiometric measurements to determine the electrode's response to nitrate ion concentration.

Main Results:

• The optimized electrode composition showed a linear Nernstian slope of -58.8 mV decade(-1) for nitrate concentrations from 2 x 10(-5) to 1 x 10(-1) mol dm(-3).
• The electrode exhibited a rapid response time of less than or equal to 10 seconds.
• The electrode operated effectively within a pH range of 5.3-11 and showed improved selectivity against common interfering ions.

Conclusions:

• The developed nitrate-selective electrode based on the [(haacac)Pb] complex offers a promising alternative for nitrate determination.
• The electrode exhibits favorable potentiometric properties, including linearity, rapid response, and good selectivity.
• This new electrode design contributes to advancements in ion-selective electrode technology for environmental and analytical applications.