分散方式对PEMFC微孔层油墨流变特性与微结构的影响研究

Effect of Dispersion on Rheological Properties and Microstructure of PEMFC Microporous Layer Ink

制备高性能的微孔层对于提升质子交换膜燃料电池性能至关重要,其中微孔层油墨的制备是微孔层制备中的核心环节,油墨的分散方式和分散时长均会影响微孔层的性能。在本文中,研究了在两种不同的分散方式及三种不同分散时长下:超声分散(15 min,30 min,45 min)和球磨分散(1 h,2 h,3 h),对微孔层性能的影响,并对微孔层油墨进行了流变性研究、粒径分布和形貌表征以及BET测试。研究结果表明:球磨分散与超声分散制备的微孔层油墨呈现不同的流变性,前者黏度20 m Pa·s明显高于后者2 mPa·s,粒径分布也因分散方式不同呈现明显差异。球磨分散方式制备的微孔层表面出现明显的团聚絮状物,增加了表面粗糙度,同时该制备方式下的微孔层比表面积为9.2922 m^(2)·g^(-1)。同样制备时长也会对微孔层性能产生影响,研究发现球磨分散2 h制备的微孔层展示了更高的优越性。

Fabricating high-performance microporous layers is essential to improve the performance of proton exchange membrane fuel cells,of which the fabrication of microporous layer inks is a central part.In this paper,the effects of two different dispersion methods and three different dispersion times:sonication(15 min,30 min,45 min)and ball milling(1 h,2 h,3 h)on the performance of the microporous layer were investigated,and the ink was subjected to rheological studies,particle size distribution and morphological characters as well as BET tests.The results show that the rheological properties of the microporous layer inks fabricated by ball milling and sonication are different,the viscosity of the former was significantly higher at 20 mPa.s than the latter at 2 mPa-s,and the particle size distribution also showing significant diferences depending on the dispersion method.The surface roughness of the microporous layer was increased by the presence of agglomerated focs on the surface of the layer prepared by ball milling,while the porosity of the layer fabricated by this method was 9.2922 m^(2)·g^(-1).The length of fabrication also had an impact on the performance of the microporous layer,and it was found that the microporous layer fabricated by ball milling for 2 h showed a higher degree of superiority.