Charge Control in Two Isostructural Anionic/Cationic CoII Coordination Frameworks for Enhanced Acetylene Capture
Di-Ming Chen1, Jia-Yue Tian1, Chun-Sen Liu2
1Henan Provincial Key Laboratory of Surface & Interface Science, Zhengzhou University of Light Industry, Zhengzhou, 450002, China.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|September 6, 2016
Summary
Two novel metal-organic frameworks (MOFs) with opposite charges were synthesized. The cationic MOF demonstrates significantly enhanced acetylene (C2H2) adsorption compared to its anionic counterpart.
Area of Science:
- Materials Science
- Chemistry
Background:
- Metal-organic frameworks (MOFs) are crystalline porous materials with diverse applications.
- Controlling framework charge is a key strategy for tuning MOF properties.
- Acetylene (C2H2) adsorption is crucial for gas storage and separation.
Purpose of the Study:
- To construct isostructural Co(II)-based MOFs with opposite framework charges.
- To investigate the influence of framework charge on C2H2 adsorption capacity.
- To elucidate the mechanism of C2H2 binding within the MOFs.
Main Methods:
- Synthesis of two bifunctional ligands with tetrazolyl or triazolyl terminals.
- Construction of isostructural cationic and anionic Co(II)-based MOFs.
- Gas adsorption measurements at various temperatures.
- Theoretical calculations (e.g., DFT) to understand adsorption mechanisms.
Main Results:
- Two isostructural Co(II)-MOFs with opposite framework charges were successfully synthesized by modifying ligand terminals.
- The cationic MOF exhibited an 88% increase in C2H2 uptake compared to the anionic MOF at 298 K.
- The cationic MOF achieved high C2H2 uptakes of 225 cm3 g-1 at 273 K and 163 cm3 g-1 at 298 K.
- Theoretical calculations revealed the crucial roles of nitrate and triazolyl groups in C2H2 binding.
Conclusions:
- Framework charge significantly impacts C2H2 adsorption in these MOFs.
- The cationic MOF shows exceptional C2H2 adsorption performance without open metal sites.
- These findings offer insights into designing MOFs for selective gas adsorption applications.
Keywords:
acetylene storagebifunctional ligandcharge controlmetal-organic frameworkssorption mechanismMore Related Videos
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