A facile, seed-mediated growth method and postannealing treatment have been employed to synthesize a single-phase 40% mass loading intermetallic Pt₃Co/Vulcan electrocatalyst, enabling the electrocatalytic layer to be thinner and thus lowering the mass transport resistance for the ORR in proton exchange membrane fuel cells (PEMFCs). These 40% Pt₃Co/C nanocatalysts exhibited superior kinetics toward the ORR, relative to a 20% Pt₃Co/C catalyst, and only showed a slight degradation in the half-wave potential and electrochemical surface area after a 4000-cycle stability test. The high activity and stability are attributed to a stable intermetallic Pt₃Co core with a Pt shell two to three atomic layers thick, as well as to its good dispersion on the support. This seed-mediated growth approach and postannealing treatment provide a new strategy to ensure single-phase formation and uniform particle size distribution for other high-mass-loading binary intermetallic/alloy electrocatalyst systems and can contribute to the practical commercialization of PEMFCs, especially in high-current-density applications, such as automotive.

中文翻译：

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高负载金属间Pt ₃ Co / C核壳纳米粒子作为增强活性的氧还原反应（ORR）电催化剂

已采用一种简便的，种子介导的生长方法和后退火处理来合成单相40％质量负载的金属间Pt ₃ Co / Vulcan电催化剂，从而使电催化层更薄，从而降低了ORR的质量传递阻力。质子交换膜燃料电池（PEMFC）。相对于20％Pt ₃ Co / C催化剂，这些40％Pt ₃ Co / C纳米催化剂对ORR表现出优异的动力学，并且在经过4000次循环稳定性后仅显示出半波电势和电化学表面积的轻微降解测试。高活性和稳定性归因于稳定的金属间Pt ₃Co核的铂壳厚度为2至3个原子层，并能很好地分散在载体上。这种种子介导的生长方法和后退火处理提供了一种新策略，可确保其他高质量负载的二元金属间金属/合金电催化剂系统的单相形成和均匀的粒径分布，并有助于PEMFC的实际商业化，尤其是在高燃料电池中。电流密度应用，例如汽车。