고온 고분자 전해질 연료전지를 위한 cathode 전극 최적화

Abstract

In an electrode, the electrochemical reactions occur in the presence of the three phase boundary (TPB), where an electrocatalyst, electrolytes, and a reactant all contact. Amounts of TPB play an important role in the fuel cell performance. One significant factor to affect amounts of TPB is a method of catalyst layer deposition. In this study, cathode gas diffusion electrodes (GDEs) prepared with various catalyst layer deposition techniques such as spraying, blade coating, and screen printing were investigated to optimize the performance of phosphoric acid-doped polybenzimidazole-based high temperature polymer electrolyte membrane fuel cell. The properties of catalyst layer in GDE were evaluated by electrochemical analysis and structure characterization. The result showed that in the case of GDE manufactured by spraying is more attractive than the other two deposition techniques. Furthermore, the influence of the wettability of cathode catalyst layer on fuel cell performance by controlling the contents of two binders (PVDF and PTFE) in catalyst layer was also studied. The results real the change in ratio of two binders with different wettabilities respectively had an impact on the charge transfer resistance of the anode electrode.