Titanate-grafted carbon black-facilitated MPLs for advanced proton exchange membrane fuel cells

Abstract

This study introduces a novel hydrophobic modification for microporous layers (MPLs) in proton exchange membrane fuel cells (PEMFCs), utilizing a chemical grafting method with Titanate coupling agent NDZ-201 on carbon black. This method overcomes the drawbacks of traditional MPLs that use polytetrafluoroethylene (PTFE) and require high-temperature post-processing, which can lead to pore blockage. The treated carbon black exhibits outstanding hydrophobic properties, enhancing both water and gas flow through the cell, thereby significantly boosting its electrochemical capabilities. With an ideal carbon loading of 2 mg cm⁻² for MPL, the cell delivers an impressive peak power density of 1045.8 mW cm⁻². The treatment also increases the contact angle of the carbon black from 65° to 156°, achieving superhydrophobicity through covalent bonding with NDZ-201. This fluorine-free, covalent grafting approach presents a new method for the development of MPLs for PEMFCs, facilitating performance improvement and sustainability. The study highlights the significance of the intricate interplay among various factors, including chemical grafting for hydrophobicity, carbon loading and open pores, affecting fuel cell performance.