Teng Juejin, Wang Min, Dai Quanbin, Wang Yilin, Sun Enyang, Wu Mingbo, Li Zhongtao
State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering, China University of Petroleum (East China), Qingdao, 266580, P.R. China.
School of Chemical Engineering, University of New South Wales Sydney, New South Wales, 2052, Australia.
Angew Chem Int Ed Engl. 2025 Jul 25:e202507604. doi: 10.1002/anie.202507604.
In proton exchange membrane fuel cells (PEMFCs), ionomer aggregation on Pt/C catalysts leads to increased oxygen transport resistance of conventional catalyst layers. This behavior significantly influences oxygen transport in the microenvironment at the triple-phase interface of Pt/C catalysts. To address this challenge, triazine-based covalent organic frameworks (COFs) were incorporated into the cathode catalyst layer, so that their well-defined pore structure and proton eligible triazine sites interact with terminal sulfonate groups of the Nafion ionomer. This interaction regulates the triple-phase microenvironment, enhances Pt utilization, and establishes directed oxygen-enriched transport channels. Under low-platinum loading conditions (-0.05 mg cm) in a H─O PEMFC, the COF-modified system achieved a peak power density of 1.55 W cm, 1.3 times of conventional PEMFCs, with a 38% reduction in local oxygen transport resistance. This work presents a new design principle for high-performance low-platinum PEMFCs, as a new approach to further advance their commercialization.
在质子交换膜燃料电池（PEMFC）中，Pt/C催化剂上的离聚物聚集会导致传统催化剂层的氧传输阻力增加。这种行为显著影响了Pt/C催化剂三相界面微环境中的氧传输。为应对这一挑战，将基于三嗪的共价有机框架（COF）引入阴极催化剂层，使其明确的孔结构和质子活性三嗪位点与Nafion离聚物的末端磺酸根基团相互作用。这种相互作用调节了三相微环境，提高了Pt的利用率，并建立了定向富氧传输通道。在H─O PEMFC的低铂负载条件（-0.05 mg cm）下，COF改性系统实现了1.55 W cm的峰值功率密度，是传统PEMFC的1.3倍，局部氧传输阻力降低了38%。这项工作提出了一种用于高性能低铂PEMFC的新设计原则，作为进一步推动其商业化的新方法。
