Pt-based alloys have been widely used as high-performance electrocatalysts for the oxygen reduction reaction (ORR). These catalysts contained high Pt contents, typically 60–70 at.% or higher, since further decreasing Pt contents would significantly lower the desired electro-catalytic activity. High-entropy alloys (HEAs) with built-in stability through their low free-energy phases provided a promising route to prepare Pt-based alloy catalysts with less than 50 at.% Pt while maintaining high ORR activity and stability in various environments. In this work, we reported a top-down de-alloying synthetic method to controllably incorporate five immiscible metals in one nanoscale solid phase. By predetermining four elements (Al, Cu, Ni and Pt) and alternating the fifth element including Pd, V, Co, Mn, etc., a series of nanoporous HEAs (np-HEAs) with Pt content of ~20–30 at.% were obtained. Among these quinary alloys, the Al-Cu-Ni-Pt-Mn np-HEA exhibited the best ORR catalytic activity and electrochemical cycling durability, well exceeding the commercial Pt/C catalysts. We expected these nanostructured HEA would offer a new class of alloy catalysts in many electrochemical reactions.

铂基合金已被广泛用作氧还原反应（ORR）的高性能电催化剂。这些催化剂含有较高的Pt含量，通常为60-70 at。％或更高，因为进一步降低Pt含量会大大降低所需的电催化活性。具有低自由能相的内在稳定性的高熵合金（HEA）为制备Pt含量低于50 at。％的Pt基合金催化剂提供了一条有希望的途径，同时在各种环境中保持了高ORR活性和稳定性。在这项工作中，我们报告了一种自上而下的脱合金合成方法，可控地将五种不混溶的金属掺入一个纳米级固相中。通过预先确定四个元素（Al，Cu，Ni和Pt）并交替包含Pd，V，Co，Mn等第五个元素，获得了一系列的Pt含量约为20–30 at。％的纳米多孔HEA（np-HEA）。在这些五元合金中，Al-Cu-Ni-Pt-Mn np-HEA表现出最佳的ORR催化活性和电化学循环耐久性，远远超过了商用Pt / C催化剂。我们预期这些纳米结构的HEA将在许多电化学反应中提供一类新型的合金催化剂。