质子交换膜燃料电池膜电极制备方法及部分改进策略

PEMFC membrane electrode assembly fabrication and improvement strategies

燃料电池被认为是21世纪最具有发展前景的能量转换装置,可应用于汽车、电站及家庭用电等领域。膜电极(membrane electrode assembly,MEA)是燃料电池电化学反应发生的主要场所,它的材料、结构、组成和制备方法等因素对燃料电池的性能有着直接的影响。膜电极制备方法可以分为催化剂制备到基体上(catalyst-coated substrate,CCS)和催化剂制备到膜上(catalyst-coated membrane,CCM)法两类。本文首先简单地介绍了CCS和CCM法中都用到的溅射法、喷涂法和转印法,再从膜电极制备方法中存在的问题出发,总结了部分有关改善MEA性能的策略,包括Nafion含量的优化、质子交换膜的改进、热压条件的优化和催化剂层的改进。在催化剂层的改进部分,分别从梯度结构、纳米结构薄膜(nano-structured thin film,NSTF)催化剂、碳纸上原位生长碳纳米管、碳纳米管/碳纳米纤维复合网状物和活性金属沉积方法这几个方面来进行阐述。

Fuel cell is considered as one of the most promising 21st century energy conversion device.It can be applied to cars,power plants and household electricity generation.Membrane electrode assembly（MEA）,in which electrochemical reaction takes place,is an essential part of the fuel cell.Materials,structure and components.used in the MEA and fabrication methods have direct influence on the performance of fuel cells.MEA preparation methods can be classified into two categories,catalyst-coated substrate（CCS） and catalyst-coated membrane（CCM） methods.The sputtering method,spraying method and decal method used in the CCS and CCM methods are described.Based on existing problems in MEA preparation,several strategies for improving MEA performance,including the optimization of nafion content and hot pressing conditions and the improvement of catalyst layer and proton exchange membrane are summarized.The catalyst layer optimization is discussed from gradient structure,3M’s nano-structured thin film（NSTF） catalyst,carbon paper on which carbon nanotubes directly grow,carbon nanotubes/carbon nanofibers composite network and the improved deposition methods of active metal.