A Cu-based bimetallic hollow structure can be effectively used to enhance the selective oxidation and electrocatalytic activity of a catalyst and to reduce its cost. In this paper, we developed a facile and scalable method for the construction of CuAu bimetallic hollow particles from Cu₂O nanoparticle aggregates (NPAs). The synthetic process includes Au growth on the Cu₂O NPA surface and silica encapsulation, which is followed by polyol reduction of Cu₂O, calcination in air and etching of the SiO₂ layer. The obtained hollow CuAu NPs (average diameter of 540 nm and wall thickness of 60 nm) outperform hollow Cu NPs in terms of catalytic activity in the reduction of 4-nitrophenol by NaBH₄ in aqueous solution. The activity factors (K = 354 and 255 s⁻¹ g⁻¹) are 2.4 and 1.7 times larger than that of the hollow Cu catalyst, depending on the Au content in the CuAu particles. In addition, the prepared catalyst was stable in the reaction system and can be recycled via centrifugation without a significant loss of catalytic activity.

中文翻译：

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具有高催化活性的中空多孔Cu-Au颗粒，可还原4-硝基苯酚

铜基双金属空心结构可有效地用于增强催化剂的选择性氧化和电催化活性并降低其成本。在本文中，我们开发了一种从Cu ₂ O纳米颗粒聚集体（NPA）构造CuAu双金属空心颗粒的简便且可扩展的方法。合成过程包括在Cu ₂ O NPA表面生长Au和二氧化硅包封，然后多元醇还原Cu ₂ O，在空气中煅烧和SiO ₂层蚀刻。就NaBH ₄还原4-硝基苯酚的催化活性而言，所得空心CuAu NPs（平均直径为540 nm，壁厚为60 nm）优于空心Cu NPs。在水溶液中。取决于CuAu颗粒中的Au含量，活性因子（K = 354和255 s ^-1 g ^-1）是空心Cu催化剂的2.4和1.7倍。另外，所制备的催化剂在反应体系中是稳定的，并且可以通过离心回收而不会显着降低催化活性。