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Updated: May 26, 2026
11:27
Synthesis and Characterization of Functionalized Metal-organic Frameworks
Published on: September 5, 2014
Formaldehyde encapsulated in lithium-decorated metal-organic frameworks: a density functional theory study
Thana Maihom1, Saowapak Choomwattana, Pipat Khongpracha
1Laboratory for Computational and Applied Chemistry, Department of Chemistry, Faculty of Science and Center of Nanotechnology, Research and Development Institute, Kasetsart University, Bangkok 10900, Thailand.
Summary
Lithium-decorated metal-organic framework Li-MOF-5 enhances formaldehyde stability. Calculations show Li-MOF-5 significantly increases the activation energy for formaldehyde trimerization, suggesting its potential for monomeric formaldehyde preservation.
Area of Science:
- Computational Chemistry
- Materials Science
- Chemical Engineering
Background:
- Formaldehyde is a reactive molecule prone to trimerization.
- Metal-organic frameworks (MOFs) offer tunable environments for chemical stabilization.
- Lithium-decorated MOFs present unique properties for guest molecule interactions.
Purpose of the Study:
- To investigate the stability of monomeric formaldehyde encapsulated in Li-MOF-5.
- To assess the efficiency of Li-MOF-5 for preserving formaldehyde in its monomeric form.
- To analyze the reaction kinetics and thermodynamic equilibrium of formaldehyde trimerization within Li-MOF-5.
Main Methods:
- Density functional calculations using the M06-L functional and 6-31G(d,p) basis set.
- Analysis of reaction kinetics and thermodynamic equilibrium for formaldehyde trimerization.
- Comparison of activation energies and Gibbs free energy between bare formaldehyde and encapsulated formaldehyde in Li-MOF-5.
Main Results:
- Formaldehyde trimerization in Li-MOF-5 has a calculated activation energy of 34.5 kcal/mol, which is 17.2 kcal/mol higher than in the bare system.
- The trimerization reaction within Li-MOF-5 is endothermic (6.1 kcal/mol) with a positive Gibbs free energy (11.0 kcal/mol).
- The reverse reaction rate (de-trimerization) is predicted to be significantly faster than the forward rate, indicating a reversible process.
Conclusions:
- Li-MOF-5 significantly enhances the kinetic stability of monomeric formaldehyde against trimerization.
- The thermodynamic analysis suggests that Li-MOF-5 favors the monomeric form of formaldehyde.
- Li-MOF-5 is a promising candidate material for the effective preservation of formaldehyde in its monomeric state.
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