초록 |
To enhance the properties of Nafion-based membrane as proton exchange membrane in fuel cells, dopamine sulfonated ceria (CeO2-DS) nanoparticles were synthesized via surface functionalization, then were embedded into thin surface layers of Nafion membranes, resulting in the sandwiched structure. The CeO2-DS nanoparticles exhibited an excellent free radical scavenging effect to enhance chemical stability, accompanied by a simultaneous improvement of proton conductivity of the membrane. The proton conductivity of the Nafion-CeO2-DS8 membrane was about 1.5-fold higher than that of pristine Nafion membrane. Nevertheless, the prepared sandwiched structure membrane demonstrated quite high electrical resistance due to the sandwiched structure. Consequently, not only the durability but also the cell performance of the membrane was significantly enhanced, illustrating the maximum power density of 522 mW cm-2, which was much higher than those of the pristine and single-layer composite membranes. |