Poly(1,5-diaminoanthraquinone)-Modified Gas Diffusion Backing by Electrochemical Deposition

Abstract

In this study, poly(1,5-diaminoanthraquinone) (P15DAAQ) was deposited on carbon fiber of gas diffusion backing (GDB) by electrochemical deposition to improve the water management ability of the gas diffusion layer (GDL). The morphology of carbon fibers of GDB was characterized by scanning electron microscopy, and the pore structure of GDBs was characterized by microcomputed tomography. The polarization curve and the limiting current method were used to study the performance and water management capabilities of proton exchange membrane fuel cells. The results show that the performance of P15DAAQ-GDB is better than that of traditional GDB modified by hydrophobic treatment with polytetrafluoroethylene (PTFE) under high relative humidity and high current density. The highest power density reaches 1.984 W·cm–2, which is 41.3% higher than that obtained under traditional PTFE hydrophobic treatment. The oxygen mass transfer resistance of P15DAAQ-GDL is smaller than that of PTFE-GDL, and the dry region (<4240 mA·cm–2) is wider than that of PTFE-GDL (<3600 mA·cm–2). These results indicate that P15DAAQ-GDL exhibits better oxygen mass transfer and water management capabilities thanPTFE-GDL.