Study On Preparation And Performance Of Nafion/TiO₂ Composite Membrane For PEMFC

Proton exchange membrane fuel cell (PEMFC) has significant advantages such as high power density, low operating temperature and excellent stability. PEMFC has a bright future in areas such as astronavigation, submarine and electric vehicles. In order to bring the commercialization of PEMFC into reality, researchers all over the world are endeavoring to develop relative materials to decrease the cost and improve the performance of PEMFC.This paper presents a sol-gel process for the preparation of Nafion/TiO2 composite membrane. XRD and ESEM were used to study the physical chemistry capability of composite films. The experiment results demonstrated that the crystal structure of TiO2 was anatase, TiO2 exhibited symmetrical distribution and the content of Ti enhanced with the increase of thickness of composite membrane.The performance of Nafion/TiO2 composite membrane mainly related to the content of TiO2. The influence of the concentration of Ti (OBu)4 on performance of composite membranes was investigated in this article. As shown in the experiment results, a medium impregnation of titanium oxide could improve the capability of Nafion film. The optimum range of concentration was confirmed.The self-humidifying capability of composite membranes was shown in this paper. The polarization characteristic of MEA with composite membrane was evaluated using the polarization plot of a single PEMFC. The experiment results indicated that the performance between MEA prepared with composite without humidification and MEA with Nafion membrane under humidification had little difference, which ascertained the water management ability of TiO2.The article also researched the performance of MEA with composite membrane during a long running time and the influence of temperature of cell on the performance of MEA. As shown in the results, MEA with composite membrane showed favorable stability after a long time and the change of temperature did not have a great impact on the performance of MEA. This result could be mainly attributed to the effect of TiO2.