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Updated: Dec 28, 2025
09:11
Raman and IR Spectroelectrochemical Methods as Tools to Analyze Conjugated Organic Compounds
Published on: October 12, 2018
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Geometrical Isomerism Directed Electrochemical Sensing.
Alagar Raja Kottaichamy1, Shabbah Begum1, Mruthyunjayachar Chattanahalli Devendrachari1
1Indian Institute of Science Education and Research (IISER) Pune, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India.
Analytical Chemistry
|February 19, 2020
Summary
Isomerism, not just the type of chemical group, significantly impacts molecular catalysts for electrochemical sensing. This study shows how isomerism redefines electronic structure, enabling sensitive detection of arsenic(III) for water remediation.
Area of Science:
- Electrochemistry
- Analytical Chemistry
- Materials Science
Background:
- Molecular electrocatalysis is crucial for electrochemical sensing.
- The role of substituent isomerism in catalyst design is often overlooked.
- Understanding electronic structure modifications is key to catalyst optimization.
Purpose of the Study:
- To investigate the independent effect of isomerism of secondary sphere substituents on molecular catalysts.
- To demonstrate how isomerism influences the electronic structure and catalytic activity.
- To develop a nonprecious molecular catalyst for electrochemical sensing of arsenic(III).
Main Methods:
- UV-vis spectroscopy to analyze electronic transitions.
- X-ray photoelectron spectroscopy (XPS) to probe electronic structure.
- Electrocatalytic studies for multi-electron oxidation of arsenic(III).
Main Results:
- Isomerism of substituents redefines the electronic structure at the catalytic center.
- Substituent isomerism influences molecular planarity and catalytic activation through field and resonance effects.
- Demonstrated isomerism-dependent oxidative activation for arsenic(III) detection.
Conclusions:
- Isomerism is a critical factor in designing molecular electrocatalysts for sensing applications.
- A nonprecious molecular catalyst with isomerism-controlled activation achieved a low detection limit for arsenic(III).
- This work offers a novel approach for developing sensing platforms for challenging electrochemical reactions.
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