Covalently grafted MOP-on-MOF hybrid ionic-porous composite for efficient adsorption and catalysis

Area of Science:

• Materials Science
• Nanotechnology
• Chemistry

Background:

• Developing multifunctional hybrid porous materials with enhanced properties is challenging due to limited synthetic methods.
• Metal-organic polyhedra (MOPs) and metal-organic frameworks (MOFs) are promising porous materials, but their integration into composites often faces issues like aggregation and leaching.

Purpose of the Study:

• To present a facile design principle for constructing multifunctional hybrid ionic porous composite materials.
• To create a MOP-on-MOF hybrid nanocomposite with enhanced physicochemical properties and stability.
• To explore the potential applications of these nanocomposites in selective adsorption and heterogeneous catalysis.

Main Methods:

• Utilized dynamic covalent chemistry, specifically strong secondary amide bonds, for covalent linking.
• Synthesized Zr-MOP-NH2 on Ti-MIL-125-NH2 via covalent grafting and electrostatic-driven assembly.
• Employed organic linkers to facilitate the assembly process.

Main Results:

• Achieved tunable enhanced physicochemical properties in the hybrid nanocomposite while maintaining the parent MOF's structure, morphology, porosity, and stability.
• Successfully prevented aggregation and leaching of MOPs within the composite structure.
• Demonstrated significantly improved selective adsorption of polyiodide species and efficient heterogeneous catalysis for nerve agent hydrolysis with high selectivity and recyclability.

Conclusions:

• The covalently grafted MOP-on-MOF strategy provides a robust method for creating novel multifunctional porous materials.
• These hybrid nanocomposites show great potential for radioiodine sequestration from water and as platforms for catalytic degradation of toxic nerve agents.
• This approach offers a promising pathway for designing advanced materials with diverse applications.