Center for Materials Chemistry, Frontier Institute of Science and Technology, and State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710054, China.
Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123, China.
Chem Rev. 2021 Jan 27;121(2):834-881. doi: 10.1021/acs.chemrev.0c00237. Epub 2020 Jun 25.
Metal nanoparticles have drawn great attention in heterogeneous catalysis. One challenge is that they are easily deactivated by migration-coalescence during the catalysis process because of their high surface energy. With the rapid development of nanoscience, encapsulating metal nanoparticles in nanoshells or nanopores becomes one of the most promising strategies to overcome the stability issue of the metal nanoparticles. Besides, the activity and selectivity could be simultaneously enhanced by taking advantage of the synergy between the metal nanoparticles and the encapsulating materials as well as the molecular sieving property of the encapsulating materials. In this review, we provide a comprehensive summary of the recent progress in the synthesis and catalytic properties of the encapsulated metal nanoparticles. This review begins with an introduction to the synthetic strategies for encapsulating metal nanoparticles with different architectures developed to date, including their encapsulation in nanoshells of inorganic oxides and carbon, porous materials (zeolites, metal-organic frameworks, and covalent organic frameworks), and organic capsules (dendrimers and organic cages). The advantages of the encapsulated metal nanoparticles are then discussed, such as enhanced stability and recyclability, improved selectivity, strong metal-support interactions, and the capability of enabling tandem catalysis, followed by the introduction of some representative applications of the encapsulated metal nanoparticles in thermo-, photo-, and electrocatalysis. At the end of this review, we discuss the remaining challenges associated with the encapsulated metal nanoparticles and provide our perspectives on the future development of the field.
金属纳米粒子在多相催化中引起了极大的关注。其中一个挑战是，由于其高表面能，它们在催化过程中很容易通过迁移-聚合并失活。随着纳米科学的快速发展，将金属纳米粒子封装在纳米壳或纳米孔中成为克服金属纳米粒子稳定性问题的最有前途的策略之一。此外，还可以利用金属纳米粒子与封装材料之间的协同作用以及封装材料的分子筛分性能来同时提高活性和选择性。在这篇综述中，我们全面总结了封装金属纳米粒子的合成和催化性能的最新进展。本综述首先介绍了迄今为止开发的不同结构封装金属纳米粒子的合成策略，包括它们在无机氧化物和碳纳米壳、多孔材料（沸石、金属有机骨架和共价有机骨架）和有机胶囊（树枝状大分子和有机笼）中的封装。然后讨论了封装金属纳米粒子的优点，例如增强的稳定性和可回收性、提高的选择性、强的金属-载体相互作用以及实现串联催化的能力，随后介绍了封装金属纳米粒子在热、光和电催化中的一些代表性应用。在这篇综述的最后，我们讨论了与封装金属纳米粒子相关的剩余挑战，并对该领域的未来发展提出了我们的看法。
