폴리도파민 기능성 코팅을 통한 기체확산층의 친수성 제어

초록

The gas diffusion layer (GDL) is an important component in fuel cells including proton exchange membrane fuel cell (PEMFC). This GDL is required a porous structure, high thermal-electrical conductivity, and electrochemical-chemical stability. In addition, the smooth supply of fuel gas (hydrogen and oxygen) and proper management of moisture generated from the electrode is also important. In this study, polydopamine (PDA) was used for functionalization to control the hydrophilicity of gas diffusion backing (GDB). The degree of PDA modification on the GDB surface was controlled according to the PDA polymerization conditions (concentration and time). Nanoscale PDA coating on the surface of carbon microfibers constituting GDB was confirmed through SEM and FT-IR analysis, and hydrophilic modification was confirmed through contact angle measurement. Changes in porous structure and electrical conductivity according to PDA coating were confirmed, and fuel cell performance was measured after the surface modifications. The PDA functionalization, we expect the enhancement of fuel cell efficiency and durability by water management in MEA and GDL.