重庆大学陈四国研究团队报道了克服离聚物对质量传递和铂活性的限制，实现高性能膜电极组装。相关研究成果发表在2024年10月22日出版的国际学术期刊《美国化学会杂志》。

膜电极组件（MEA）是质子交换膜燃料电池（PEMFCs）的关键部件之一。然而，具有覆盖型催化剂/离聚物界面结构的传统MEA阴极，严重限制了氧传输效率和Pt活性，很难达到PEMFCs的理论性能上限。

该文中，研究人员设计了一种在阴极催化剂层（CL）中具有低质子传输阻力，和高氧传输效率的非覆盖催化剂/离聚物界面结构。这种非覆盖界面结构利用离聚物交联的碳颗粒，作为长程和快速的质子传输通道，防止离聚物直接覆盖CL中的Pt/C催化剂表面，从而使氧扩散过程免于通过致密的离聚物覆盖层到达Pt表面。

此外，该结构改善了CL孔内的氧传输，与覆盖型结构相比，压力无关的氧传输阻力降低了20%以上。燃料电池检测表明，非覆盖催化剂/离聚物界面结构在动力学和质量传输受限区域，提供了卓越的燃料电池性能，在0 kPagogue氧气和空气条件下，峰值功率密度分别比覆盖型界面结构高77%和67%。这种替代界面结构，为优化电极结构和改善MEA的传质路径提供了新的方向。

附：英文原文

Title: Overcoming the Limitation of Ionomers on Mass Transport and Pt Activity to Achieve High-Performing Membrane Electrode Assembly

Author: Fadong Chen, Lin Guo, Daojun Long, Shijian Luo, Yang Song, Meng Wang, Li Li, Siguo Chen, Zidong Wei

Issue&Volume: October 22, 2024

Abstract: The membrane electrode assembly (MEA) is one of the critical components in proton exchange membrane fuel cells (PEMFCs). However, the conventional MEA cathode with a covered-type catalyst/ionomer interfacial structure severely limits oxygen transport efficiency and Pt activity, hardly achieving the theoretical performance upper bound of PEMFCs. Here, we design a noncovered catalyst/ionomer interfacial structure with low proton transport resistance and high oxygen transport efficiency in the cathode catalyst layer (CL). This noncovered interfacial structure employs the ionomer cross-linked carbon particles as long-range and fast proton transport channels and prevents the ionomer from directly covering the Pt/C catalyst surface in the CL, freeing the oxygen diffusion process from passing through the dense ionomer covering layer to the Pt surface. Moreover, the structure improves oxygen transport within the pores of the CL and achieves more than 20% lower pressure-independent oxygen transport resistance compared to the covered-type structure. Fuel-cell diagnostics demonstrate that the noncovered catalyst/ionomer interfacial structure provides exceptional fuel-cell performance across the kinetic and mass transport-limited regions, with 77% and 67% higher peak power density than the covered-type interfacial structure under 0 kPagauge of oxygen and air conditions, respectively. This alternative interfacial structure provides a new direction for optimizing the electrode structure and improving mass-transport paths of MEA.

DOI: 10.1021/jacs.4c10742

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.4c10742