乙烷质子传导膜燃料电池的极化与反应机理

Polarization and Reaction Mechanism of Proton Conducting Membrane Fuel Cell with Ethane as Fuel

制备了以乙烷作为燃料电池膜电极组装(MEA)及构建了单电池系统。研究了Nafion材料作为质子传导膜、Pt/C作为电极催化剂构成的燃料电池在105℃和0.4 MPa电化学性能。采用交流阻抗分析法、色谱分析法及根据Faraday定律,考察了电池的电极极化过程,确定了电池的反应产物并探讨了电极的电化学反应机理。研究结果表明,乙烷燃料电池内阻引起的欧姆极化很小,电池阴极的极化主要是欧姆极化过程所控制,阳极极化主要为活化和浓差过程控制,阳极极化比阴极极化显著,乙烷燃料电池的极化主要在阳极侧;在实验操作条件下,阴极反应产物为水,阳极反应的主产物为CO2且含有少量的CO,电池反应产物不含乙烯。

The membrane electrode assembly and single cell system of fuel cell were set up with ethane as fuel,and the electrochemical performance of the fuel cell with Nafion material as a proton conducting membrane and Pt/C as electrode catalysts was investigated at 105 ℃ and 0.4 MPa.The polarization processes of cathode and anode for the fuel cell were observed,the reaction products of the cell were determined and the reaction mechanism of the cell was explored by using alternating current impedance and gas chromatography as well as according to Faraday law.The experimental results showed that the ohms polarizaton induced by internal resistance of cell was quite small,the polarization of cathode lay mainly in the process control of ohms polarization,the polarization of anode focused mainly on the the process control of activity and concentration difference,the polarization of anode was reamarkablly great in comparison with that of cathode,and the polarization of cell was concentrated mostly on that of anode side.The reaction product produced from the cathode was water and the main prodcut obtained from the anode was carbon dioxide with only a small fraction of carbon monoxide and without ethylene generation.