催化层中PTFE含量对氢氧膜电极性能的影响规律

Effect of Content of PTFE in Catalyst Layer on Performance of Membrane Electrode under the Condition of Hydrogen and Oxygen

催化层中的氧传输对质子交换膜燃料电池的性能有很大的影响,将PTFE纳米颗粒加入到催化层中,制备不同含量PTFE的催化层,探究了PTFE加入对膜电极的微观结构,疏水度,孔隙率及电池性能的影响。结果表明,催化层中PTFE不会影响催化剂Pt的活性,且能均匀分散在催化层中,极化曲线结果表明,PTFE含量太少,对膜电极性能的提升没效果,但PTFE含量太多时,又会导致性能的降低。当PTFE含量为20%时,催化层中大孔和小孔的比例合适,有利于水气的传输,得到的性能最好,氢氧条件下功率密度可达到1.6W/cm^2以上。

Oxygen transmission in the catalyst layer has a great impact on the performance of the proton exchange membrane fuel cell. PTFE nanoparticles are added to the catalyst layer to prepare catalyst layer with different contents of PTFE. The effects of PTFE on the microstructure,hydrophobicity,porosity and battery performance of the membrane electrode are investigated. The results show that PTFE in catalyst layer will not affect the activity of the Pt,and it can be evenly dispersed in the catalyst layer. The polarization curve results show that when the PTFE content is too small,there is no effect on the properties of membrane electrode ascension,but when PTFE content is too much,it then lead to a drop in performance. When the PTFE content is 20%,the large pores and small pores ratio is appropriate in catalyst layer,which is benefit for the water and oxygen transport for getting the best performance. The power density under the condition of hydrogen and oxygen can reach more than 1.6 W/cm^2.