Nie Yan, Li Qiyuan, Jia Chen, Zheng Xiaoran, Shi Zhun, Wang Shuhao, Meyer Quentin, Li Xin-Hao, Zhao Chuan
School of Chemistry, University of New South Wales, Sydney, 2052, Australia.
School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Jiao Tong University, Shanghai, 200240, China.
Small. 2025 Sep 1:e05914. doi: 10.1002/smll.202505914.
Oxygen reduction reaction (ORR) performance of platinum can be improved through alloying transition metals, with L1-PtCo emerging as a standout option due to its balanced catalytic performance, durability, and manufacturability. However, traditional carbon supports often fail to stabilize nanoparticles, leading to performance degradation. This study introduces a mesoporous Co-N-C supported ordered L1-PtCo catalyst to overcome the above limitations. The CoN sites in the mesoporous Co-N-C (MS-CoNC) support create a strong synergy with L1-PtCo clusters, preventing nanoparticle aggregation during high-temperature synthesis. X-ray absorption spectroscopy reveals a unique shortened Pt-Pt bond length in L1-PtCo/MS-CoNC, which contributes to a mass activity of 0.54 A mg, 6.3 times that of commercial carbon-supported PtCo catalysts. Rationalised by density functional theory, L1-PtCo/MS-CoNC optimizes its d-band centre for enhancing ORR intermediate adsorption-desorption. Membrane electrode assemblies test deliver remarkably improved peak power density while with only 60 µg cm of Pt. The mesoporous structure of the Co-N-C support further reduces mass transport losses, enhancing oxygen diffusion and stability. Durability testing shows minimal performance loss after 30 000 voltage cycles, showcasing the catalyst's robustness under harsh PEMFC conditions. This work demonstrates the synergistic advantages of mesoporous Co-N-C supports and L1-PtCo catalysts, paving the way for high-performance, low-Pt fuel cell technologies.
通过与过渡金属合金化可以提高铂的氧还原反应（ORR）性能，其中L1-PtCo因其平衡的催化性能、耐久性和可制造性而成为突出的选择。然而，传统的碳载体往往无法稳定纳米颗粒，导致性能下降。本研究引入了一种介孔Co-N-C负载的有序L1-PtCo催化剂，以克服上述局限性。介孔Co-N-C（MS-CoNC）载体中的CoN位点与L1-PtCo簇产生强烈的协同作用，防止纳米颗粒在高温合成过程中聚集。X射线吸收光谱揭示了L1-PtCo/MS-CoNC中独特的缩短的Pt-Pt键长，这有助于实现0.54 A mg的质量活性，是商业碳负载PtCo催化剂的6.3倍。通过密度泛函理论合理化，L1-PtCo/MS-CoNC优化了其d带中心，以增强ORR中间体的吸附-解吸。膜电极组件测试在仅60 µg cm的Pt负载下显著提高了峰值功率密度。Co-N-C载体的介孔结构进一步降低了传质损失，增强了氧扩散和稳定性。耐久性测试表明，在30000次电压循环后性能损失最小，展示了该催化剂在苛刻的质子交换膜燃料电池条件下的稳健性。这项工作展示了介孔Co-N-C载体和L1-PtCo催化剂的协同优势，为高性能、低铂燃料电池技术铺平了道路。
