Isostructural Transformation From a Hydrogen-Bonded Metal-Complex Framework to a Metal-Organic Framework for Enhanced
Xiao-Li Yu1, Zongwei Jia1, Hongliang Huang2
1Key Laboratory of Eco-Chemical Engineering, Ministry of Education, International Science and Technology Cooperation Base of Eco-Chemical Engineering and Green Manufacturing, College of Chemistry and Molecular Engineering Qingdao University of Science and Technology, Qingdao, P. R. China.
Angewandte Chemie (International Ed. in English)
|April 7, 2026
Summary
A new metal-organic framework (MOF), ALP-MOF-4, demonstrates exceptional ammonia (NH3) tolerance and reversible capture. This MOF offers high NH3 storage density and effective trace NH3 removal, showing promise for durable ammonia sorption applications.
Area of Science:
- Materials Science
- Chemistry
- Chemical Engineering
Background:
- Metal-organic frameworks (MOFs) are explored for ammonia (NH3) storage and capture.
- Developing MOFs with NH3 tolerance and reversible uptake remains a challenge.
Purpose of the Study:
- To present a novel strategy for synthesizing MOFs with enhanced NH3 tolerance and reversibility.
- To investigate the NH3 adsorption properties and binding mechanisms of the new MOF.
Main Methods:
- Ligand substitution strategy to transform a hydrogen-bonded metal-complex framework (ALP-HOF-1) into a porous MOF (ALP-MOF-4).
- Ammonia adsorption/desorption cycles and breakthrough experiments to confirm NH3 tolerance and reversibility.
- X-ray photoelectron spectroscopy and computational studies to identify NH3 binding sites.
Main Results:
- ALP-MOF-4 exhibits remarkable NH3 tolerance and reversible uptake.
- High NH3 packing density at 298 K and 1.0 bar, comparable to liquid NH3.
- Cooperative action of open metal sites, carbonyl, and NH groups enables excellent trace NH3 capture (<50 ppm) from mixed gas streams.
Conclusions:
- ALP-MOF-4 demonstrates significant potential as a durable and recyclable NH3 sorbent.
- The study provides design principles for transforming HOFs to MOFs for selective gas capture.
- This work advances the development of efficient materials for ammonia storage and environmental remediation.
Keywords:
ammonia tolerancehydrogen‐bonded organic frameworksisostructural transformationligand substitutionmetal–organic frameworksMore Related Videos
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