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A Viologen-Based Metal-Organic Complex for Highly Efficient and Selective Dye Flocculation.
Xin Li1, Zi-Xuan Guo1, Chun-Li Song1
1College of Chemistry, Jilin University, Changchun, P. R. China.
Chemistry, an Asian Journal
|December 9, 2025
Summary
A novel viologen-based metal-organic complex (VIO-MOC) efficiently removes 99.9% of Congo Red dye in 30 minutes. This advanced material offers superior adsorption capacity for industrial wastewater treatment.
Area of Science:
- Materials Science
- Environmental Chemistry
- Nanotechnology
Background:
- Industrial dye wastewater poses significant environmental risks.
- Existing treatment methods often lack efficiency and selectivity.
- Novel materials are needed for effective dye removal.
Purpose of the Study:
- To design and synthesize a zero-dimensional (0D) viologen-based metal-organic complex (VIO-MOC).
- To evaluate the VIO-MOC's performance in removing Congo Red dye.
- To elucidate the synergistic coagulation-flocculation mechanism.
Main Methods:
- Synthesis of a zero-dimensional (0D) viologen-based metal-organic complex ([Cd2(μ2-Cl)Cl2Br2bpyen]).
- Performance testing for Congo Red removal efficiency and adsorption capacity.
- Characterization using Zeta potential, FTIR spectroscopy, and DFT calculations.
Main Results:
- Achieved 99.9% Congo Red removal efficiency within 30 minutes.
- Demonstrated a maximum adsorption capacity of 3080.6 mg/g.
- Confirmed a synergistic mechanism involving π-π stacking, electrostatic interactions, and hydrogen bonding.
Conclusions:
- VIO-MOC exhibits exceptional performance for dye wastewater treatment.
- The material shows stable performance across a wide pH range (5-11) and tolerance to inorganic ions.
- This study provides a blueprint for designing functionalized metal-organic complexes for environmental remediation.
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