Phase engineering is arising as an attractive strategy to tune the properties and functionalities of nanomaterials. In particular, amorphous/crystalline heterophase nanostructures have exhibited some intriguing properties. Herein, the one-pot wet-chemical synthesis of two types of amorphous/crystalline heterophase PdCu nanosheets is reported, in which one is amorphous phase-dominant and the other one is crystalline phase-dominant. Then the aging process of the synthesized PdCu nanosheets is studied, during which their crystallinity increases, accompanied by changes in some physicochemical properties. As a proof-of-concept application, their aging effect on catalytic hydrogenation of 4-nitrostyrene is investigated. As a result, the amorphous phase-dominant nanosheets initially show excellent chemoselectivity. After aging for 14 days, their catalytic activity is higher than that of crystalline phase-dominant nanosheets. This work demonstrates the intriguing properties of heterophase nanostructures, providing a new platform for future studies on the regulation of functionalities and applications of nanomaterials by phase engineering.

中文翻译：

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用于催化反应的老化非晶/结晶异相 PdCu 纳米片

相工程作为调整纳米材料特性和功能的一种有吸引力的策略而出现。特别是，非晶/结晶异相纳米结构表现出一些有趣的特性。本文报道了两种非晶/结晶异相 PdCu 纳米片的一锅法湿化学合成，其中一种以非晶相为主，另一种以晶相为主。然后研究了合成的 PdCu 纳米片的老化过程，在此过程中它们的结晶度增加，伴随着一些物理化学性质的变化。作为概念验证应用，研究了它们对 4-硝基苯乙烯催化氢化的老化影响。结果，非晶相占主导地位的纳米片最初表现出优异的化学选择性。陈酿14天后，它们的催化活性高于以晶相为主的纳米片。这项工作证明了异相纳米结构的有趣特性，为未来通过相工程调节纳米材料的功能和应用提供了新的平台。