Presentation Information
[9a-P01-9]Effect of Stacked Structure of GO and MMT composite on Proton Pathways in Proton Exchange Membranes
〇(DC)Beshoy Thapet Nasr1, Kanishka De Silva1, Masanori Hara1, Chinnasamy Sengottaiyan1, Masamichi Yoshimura1 (1.Toyota Technological Institute)
Keywords:
fuel cell
Fuel cell membranes are crucial for proton conductivity, which directly impacts fuel cell performance. Recent studies have focused on improving proton conductivity and mechanical properties by incorporating fillers like graphene oxide (GO)¹ and montmorillonite (MMT)² clay into polymer membranes. These fillers enhance proton conductivity through their unique structures and ability to increase water uptake. However, the alignment and orientation of the membrane's internal structure, a key factor in proton pathway efficiency, have been largely overlooked. This study investigates the effect of membrane morphology on proton conductivity in fuel cell membranes. Membranes with different layer numbers were prepared using a layer-by-layer (LBL) solution casting technique.
Fig. 1 shows the difference in morphology between the membranes prepared by the LBL method (a) and the mixed method (b). In this study, an experiment was conducted to measure proton conductivity using electrochemical impedance spectroscopy (Fig. 2). The impedance in the mixed membrane is notably higher than that in the LBL membrane, confirming reduced efficiency of proton transport in the disordered structure. The proton conductivity measurements showed a clear increase with the number of layers. The 4-layer (4L) membrane demonstrated the highest conductivity, reaching 21 S/m, compared to 1.8 S/m in the mixed membrane under identical conditions. The 4L membrane’s performance stems from stronger hydrogen bonding between layers and a continuous, ordered proton pathway. These factors enhance water retention and boost proton transfer. The results prove that increasing aligned, stacked layers markedly improve membrane structure and fuel cell performance.
Fig. 1 shows the difference in morphology between the membranes prepared by the LBL method (a) and the mixed method (b). In this study, an experiment was conducted to measure proton conductivity using electrochemical impedance spectroscopy (Fig. 2). The impedance in the mixed membrane is notably higher than that in the LBL membrane, confirming reduced efficiency of proton transport in the disordered structure. The proton conductivity measurements showed a clear increase with the number of layers. The 4-layer (4L) membrane demonstrated the highest conductivity, reaching 21 S/m, compared to 1.8 S/m in the mixed membrane under identical conditions. The 4L membrane’s performance stems from stronger hydrogen bonding between layers and a continuous, ordered proton pathway. These factors enhance water retention and boost proton transfer. The results prove that increasing aligned, stacked layers markedly improve membrane structure and fuel cell performance.