Polybenzimidazole/Mxene composite membranes for intermediate temperature polymer electrolyte membrane fuel cells

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Intermediate temperature polymer electrolyte membrane fuel cells (ITPEMFCs) require advanced membrane materials for improved performance.
• Polybenzimidazole (PBI)-based membranes are suitable for ITPEMFCs but can be further enhanced.

Purpose of the Study:

• To investigate the potential of MXene as a filler for enhancing PBI-based membranes in ITPEMFCs.
• To evaluate the impact of Ti3C2Tx-MXene on proton conductivity, mechanical properties, and thermal stability.

Main Methods:

• Synthesis of Ti3C2Tx-MXene.
• Incorporation of MXene into PBI membranes using solution blending.
• Characterization of composite membrane properties (proton conductivity, mechanical strength, thermal stability).
• Testing of fuel cell performance at elevated temperatures.

Main Results:

• Composite membranes with 3 wt% Ti3C2Tx-MXene exhibited over 2x higher proton conductivity than pristine PBI from 100 °C to 170 °C.
• A ~30% increase in maximum power density was observed for fuel cells using MXene-enhanced membranes at 150 °C.
• Significant improvements in tensile strength (~150%) and Young's modulus (~160%) were achieved, with unaffected elongation at break.

Conclusions:

• Ti3C2Tx-MXene shows great promise for enhancing the performance of PBI-based membranes in ITPEMFCs.
• MXene addition improves both electrochemical and mechanical properties, making it a valuable material for fuel cell applications.