直接甲醇燃料电池用Nafion(R)ICeO2复合膜的研究

摘要

采用溶液再铸法制备了Nafion(R) ICeO2复合膜,并对该复合膜进行了热重分析法(TGA),X射线衍射法(XRD)和扫描电子显微镜法( SEM)表征,以及吸水率、质子电导率和甲醇渗透率测试.研究结果表明:与纯Nafion(R)再铸膜相比,Nafion(R) ICeO2复合膜的吸水率和质子电导率略有降低,甲醇渗透率降低.在不同CeO2含量(质量分数1％～8％)的Nafion(R) ICeO2复合膜中,复合膜的甲醇渗透率随着CeO2含量的增加而降低,其中CeO2含量为5％的复合膜表现出最高的选择性(φ=6.94×103 S/cm3).在75℃,5 mol/L甲醇进料时,与纯Nafion(R)再铸膜相比,使用CeO2含量为5％的Nafion(R) ICeO2复合膜组装的直接甲醇燃料电池单池放电峰值功率密度由67 mW/cm2提高到78 mW/cm2.%In this paper, Nation~(R) ICeO2 composite membranes were prepared by a solution casting method. The physicochemical properties of composite membranes were characterized by thermo-gravimetric analysis (TGA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The water uptake ability, proton conductivity and methanol permeability of the composite membranes were evaluated and compared with the recast Nation ~(R) membrane. The results show that the proton conductivity and the water uptake of the composite membranes are slightly lower than that of the recast Nation ? Membrane, and the methanol permeability of the composite membranes decreases with the increase of CeO2 contents. The composite membrane containing 5% CeO2 shows the highest selectivity (φ =6.94 x 103 S/cm3) among the composite membranes, and it further improves the direct methanol fuel cell (DMFC) performance (78 mW/cm2) with 5 mol/L methanol feeding, compared with the recast Nation membrane (67 mW/cm2).