Synthesis of Pt-Ni-Cu Nanocages for Efficient Oxygen Reduction Electrocatalysis

控制Pt基纳米材料的表面、形状和组成可显著提升氧还原反应的催化性能。由超薄纳米片构成的基于Pt的纳米笼，作为一种新型高效催化剂，具有较高的Pt原子利用率。然而，如何通过简单策略设计多金属纳米笼以扩展催化剂的组成空间仍然是一个挑战。在此，我们提出将溶剂热合成法与室温下的保形腐蚀相结合，实现了壁厚仅为7原子层的Pt-Ni-Cu三元纳米笼的合成。此外，通过调控表面活性剂，能有效控制Pt-Ni-Cu三元纳米笼的结构。由于其独特的结构与组成，Pt-Ni-Cu三元纳米笼在氧还原反应(ORR)中展现出优异的质量活性，0.9 V时质量活性为1411 mA·mgPt−1，是商业Pt/C催化剂的9.0倍，优于近期报道的Pt基纳米笼。Controlling the surface, shape, and composition of Pt-based nanomaterials can greatly boost oxygen reduction catalysis. Pt-based nanocages composed of ultrathin nanosheets have emerged as a new class of efficient catalysts with high atomic utilization efficiency of Pt. However, engineering multimetallic nanocages via facile strategies still remains a challenge to extend compositional space for catalyst development. Here, this work achieves the synthesis of Pt-Ni-Cu ternary nanocages with walls as thin as 7 atomic layers, by developing a general strategy that combines the solvothermal synthesis of highly composition segregated nanocrystals with the conformal corrosion at room temperature. In addition, the structure of Pt-Ni-Cu ternary nanocages can be well controlled by simply changing the surfactants. Benefiting from their unique structure and composition, the Pt-Ni-Cu ternary nanocages exhibit superior mass activity towards oxygen reduction reaction (ORR), with a value of 1411 mA·mgPt−1 at 0.9 V, which is 9.0 times higher than that of commercial Pt/C catalyst and outperforms the recently reported Pt-based nanocages.