Mg-MOF-74 Derived Defective Framework for Hydrogen Storage at Above-Ambient Temperature Assisted by Pt Catalyst

Area of Science:

• Materials Science
• Chemical Engineering
• Energy Storage

Background:

• Metal-organic frameworks (MOFs) show potential for hydrogen storage via chemisorption.
• Current modified MOFs lack sufficient hydrogen adsorption strength for practical applications.
• Existing materials do not meet capacity and safety requirements for hydrogen storage systems.

Purpose of the Study:

• To develop a novel defective MOF material for improved hydrogen storage.
• To enhance hydrogen adsorption strength and storage capacity in MOFs.
• To evaluate the material's performance for on-board hydrogen storage applications.

Main Methods:

• Preparation of a defective Mg-MOF-74 (de-MgMOF) via gentle annealing.
• Characterization of the defective framework and its hydrogen adsorption properties.
• Integration with a platinum (Pt) spillover catalyst for enhanced storage capacity.

Main Results:

• de-MgMOF exhibits strong hydrogen chemisorption with enthalpies from -22.7 to -43.6 kJ mol⁻¹.
• Achieved a reversible hydrogen storage capacity of 2.55 wt.% at 160 °C and 81 bar with Pt catalyst.
• Demonstrated rapid hydrogen uptake/release, stable cycling, and convenient storage.

Conclusions:

• The defective Mg-MOF (de-MgMOF) offers exceptional hydrogen storage capacity.
• The material's properties meet critical requirements for safe and efficient hydrogen storage.
• Techno-economic analysis indicates superior system-level performance for on-board applications.