Dibromomethane Knitted Highly Porous Hyper-Cross-Linked Polymers for Efficient High-Pressure Methane Storage

Area of Science:

• Materials Science
• Polymer Chemistry
• Chemical Engineering

Background:

• Hyper-cross-linked polymers (HCPs) are promising for methane storage due to their high porosity and stability.
• Achieving BET surface areas over 3000 m² g⁻¹ in HCPs is a significant challenge.

Purpose of the Study:

• To develop a novel method for synthesizing HCPs with ultra-high porosity.
• To enhance the methane storage capacity of HCPs.

Main Methods:

• A new DBM-knitting method using dibromomethane (DBM) as a solvent and cross-linker at a slow knitting rate.
• Synthesis of DBM-knitted SHCPs-Br and comparison with DCM-knitted SHCPs-Cl.
• Characterization of porosity (BET surface area) and methane storage capacity.

Main Results:

• DBM-knitted HCPs exhibit 44%-120% higher BET surface areas than DCM-knitted counterparts.
• SHCP-3-Br achieved an unprecedented BET surface area of 3120 m² g⁻¹.
• Competitive volumetric methane uptake of 191 cm³ (STP) cm⁻³ at 273 K and 5-100 bar, outperforming MOFs.

Conclusions:

• The DBM-knitting method with a low knitting rate effectively increases HCP porosity.
• This strategy offers a facile and versatile route to high-porosity HCPs for methane storage.
• The developed HCPs show superior performance compared to state-of-the-art materials.