화학공학소재연구정보센터
Journal of Power Sources, Vol.246, 522-530, 2014
Fabrication of phosphotungstic acid functionalized mesoporous silica composite membrane by alternative tape-casting incorporating phase inversion technique
Meso-porous silica (MCM-41) membranes functionalized by phosphotungstic acid (HPW) for high temperature proton exchange membrane fuel cells (HT-PEMFCs) are successfully developed by a cost-effective tape-casting incorporating phase inversion and vacuum assisted wet impregnation techniques. The microstructure of the membrane is characterized by field emission scanning electron microscopy (FESEM). The effect of MCM-41 content on the tensile strength, ultimate elongation, and weight gain ratio and swelling ratio in water/methanol of the membranes are investigated in detail. The thermal stability of MCM-41 membrane with/without HPW is analyzed by thermogravimetric analysis (TGA) and derivative thermogravimetry (DTG) techniques. In particular, the effects of HPW loading and MCM-41 content on the proton conductivity of HPW/MCM-41 membranes are studied comprehensively. The results on the swelling ratio and tensile tension show that the developed membranes can be applied as an electrolyte membrane for HT-PEMFCs. The developed MCM-41 membrane, in which polyethersulfone (PESf) is used as the supporting backbone, is able to operate up to 200 degrees C. The single cell assembled from HPW/MCM-41 membrane with 70 wt.% HPW loading gives a peak output power of similar to 230 mW cm(-2) and similar to 125 mW cm(-2) in H-2/air at 90 degrees C and in methanol/air at 150 degrees C without any humidification, respectively. (C) 2013 Elsevier B.V. All rights reserved.