posted on 2024-01-19, 16:36authored byWei Wang, Jie Guo, Tianyi Gu, Ruhua Shi, Xian Wei, Qian Zhang, Haibo Wang, Ruizhi Yang
The
hydrophobicity of microporous layers (MPLs) plays an important
role in water management and performance enhancement of proton-exchange
membrane fuel cells (PEMFCs). In this study, we demonstrate a facile
synthetic strategy for preparing a gradient hydrophobic MPL. The superhydrophobicity
of the MPL is achieved by chemically grafting carbon black with dodecyltrimethoxysilane
(DTMS). The MPL with gradient hydrophobicity is constructed with hydrophobic
DTMS-functionalized carbon black integrated with a fine proportion
of hydrophilic carbon black, demonstrating advanced water drainage
capability. As employed in a PEMFC, the as-fabricated gradient hydrophobic
MPL shows a significantly improved performance compared to a single
hydrophobic MPL. The PEMFC loaded with the optimum gradient hydrophobic
MPL delivers maximum power densities of 860.7 and 733.5 mW cm–2 at relative humidities (RHs) of 30 and 60%, respectively.
The results presented herein provide a new strategy for the construction
of gradient hydrophobic MPLs for adaptable PEMFCs.