Electrochemical study of chemically modified and screen-printed graphite electrodes with

Area of Science:

• Electrochemistry
• Materials Science
• Environmental Chemistry

Background:

• Sulfide detection is crucial for environmental monitoring.
• Development of stable and sensitive electrochemical sensors is needed.
• Antimony(V) complexes offer potential electrocatalytic properties.

Purpose of the Study:

• To prepare and electrochemically characterize novel graphite electrodes modified with hexadecylpyridinium-bis(chlorilato)-antimonyl(V), [SbVO(CHL)2]Hex.
• To evaluate the electrocatalytic activity of these modified electrodes for sulfide oxidation.
• To develop a reliable method for sulfide determination in simulated wastewater using screen-printed electrodes (SPEs).

Main Methods:

• Synthesis and characterization of the new compound [SbVO(CHL)2]Hex.
• Fabrication of screen-printed electrodes (SPEs) using [SbVO(CHL)2]Hex/graphite mixture.
• Electrochemical measurements including cyclic voltammetry (CV) and chronoamperometry.
• Determination of sulfide in simulated wastewater samples.
• Evaluation of method interference, linearity, precision, and recovery.

Main Results:

• The new compound [SbVO(CHL)2]Hex was successfully synthesized and characterized.
• SPEs modified with [SbVO(CHL)2]Hex demonstrated effective electrocatalysis for sulfide oxidation.
• The proposed method showed good correlation with a colorimetric method, with linearity from 0.01-0.7 mM sodium sulfide.
• High precision (CV = 2.8% for 0.1 mM Na2S) and recovery (94-102%) were achieved.
• SPEs exhibited excellent storage stability and operational stability for over 100 runs, unlike CMEs.

Conclusions:

• Screen-printed electrodes modified with [SbVO(CHL)2]Hex are effective and stable sensors for sulfide determination.
• The developed method is suitable for analyzing sulfide in simulated wastewater samples.
• SPEs offer a practical and robust alternative to CMEs for long-term electrochemical sensing applications.