Acta Chimica Sinica ›› 2023, Vol. 81 ›› Issue (9): 1135-1141.DOI: 10.6023/A23040184 Previous Articles     Next Articles

Special Issue: 庆祝《化学学报》创刊90周年合辑

Article

高温质子交换膜燃料电池中阴极双催化层孔结构的设计研究

刘士琨a, 邓程维b, 姬峰b, 闵宇霖a,*(), 李和兴a,*()   

  1. a 上海电力大学 环境与化学工程学院 上海 201306
    b 上海空间电源研究所 化学电源技术研发中心 上海 201100
  • 投稿日期:2023-04-29 发布日期:2023-07-13
  • 作者简介:
    庆祝《化学学报》创刊90周年.
  • 基金资助:
    上海市科学技术委员会(20520740900)

Design and Study on Pore Structure of Cathode Double Catalytic Layer in High-temperature Proton Exchange Membrane Fuel Cell

Shikun Liua, Chengwei Dengb, Feng Jib, Yulin Mina(), Hexing Lia()   

  1. a School of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 201306
    b Chemical Power Technology Research and Development Center, Shanghai Institute of Space Power-Sources, Shanghai 201100
  • Received:2023-04-29 Published:2023-07-13
  • Contact: *E-mail: minyulin@shiep.edu.cn; Hexing-Li@shnu.edu.cn
  • About author:
    Dedicated to the 90th anniversary of Acta Chimica Sinica.
  • Supported by:
    Shanghai Municipal Commission of Science and Technology(20520740900)

High-temperature proton exchange membrane fuel cell (HT-PEMFCs) has the advantages of simple hydro-thermal management, strong resistance to CO, direct feeding of reforming gas and high efficiency of cogeneration. It is one of the ideal power sources for the development of clean energy. As the core component of HT-PEMFCs, membrane electrode assembly (MEA) is mainly composed of cathode and anode gas diffusion electrode and proton exchange membrane, which determines the performance and cost of HT-PEMFCs. Therefore, optimizing the structure of gas diffusion electrode (GDE) is an important means to improve the performance and reduce the cost of HT-PEMFC. In this work, from the point of view of catalytic layer, pore-forming agent was introduced into catalytic layer to construct double catalytic layer with different pore structure. Among them, MEA 2 uses 46.7% (w) PtCo/C in the inner catalyst layer without adding pore-forming agent, and the outer catalyst layer uses 40% (w) Pt/C and adds 20% (w) pore-forming agent. It has relatively small ohmic polarization, minimum mass transfer polarization and activation polarization, and has the largest electrochemical active area, and the electrochemical performance is the best. At 160 ℃ and atmospheric pressure, hydrogen and air as fuel, the maximum power density of the single cell composed of the membrane electrode is 439 mW•cm-2, which is 69 mW•cm-2 higher than that of the single cell without pore-forming agent. Whether the pore-forming agent is added into the inner catalytic layer (CL) or the outer CL, the pore structure is adjusted to optimize the phosphoric acid (PA) distribution and reduce the oxygen mass transfer resistance to improve the electrochemical performance. The former catalyst layer has a greater hydrophobicity change and the electrochemical performance is more affected by the PA content, while the latter catalyst layer hydrophobicity changes less and the electrochemical performance is more affected by the oxygen mass transfer resistance. Excessive addition of pore-forming agent inside or outside CL will produce larger ohmic polarization resistance (RΩ), and the acid drowning caused by insufficient hydrophobicity of CL will further reduce the electrochemical performance of the battery.

Key words: high-temperature proton exchange-membrane fuel cell, double catalytic layer, pore-forming agent, electrochemical performance