Design of confined catalysts and applications in environmental catalysis: Original perspectives and further prospects

• Published in: Journal of cleaner production 2023-03, Vol.390, p.136125, Article 136125
• Main Authors: Zhao, Tian, Huang, Xiaosheng, Cui, Rongji, Han, Weiliang, Zhang, Guodong, Tang, Zhicheng
• Format: Article
• Language: English
• Subjects: Confinement effect; Encapsulation technique; Environmental catalysis
• ISSN: 0959-6526; 1879-1786
• DOI: 10.1016/j.jclepro.2023.136125

Catalysts play a vital role in the chemistry realm and contribute a lot to the rapid development of the industrial economy. However, traditionally supported catalysts still face severe challenges in practical applications, such as active nanoparticles being prone to migration and aggregation, poor stability, and easy poisoning and inactivation. With the introduction of the concept of ‘confined catalysis’, the use of encapsulation technology to encapsulate active nanoparticles on a carrier has become an effective strategy for designing novel and efficient catalysts. Due to the spatial confinement effect and the electronic confinement impact of the confined catalyst, the active nanoparticles are not only stabilized, but the active species' redox characteristics are also modified, thereby enhancing the overall performance of the catalyst. Therefore, researchers have developed many encapsulation techniques to improve catalyst activity, stability, and selectivity. The synthetic methods for encapsulating active particles will be the starting point in this research, and we will expound on them independently with alternative catalyst architectures. The implications of confinement catalysts on catalyst performance will be examined, including catalytic activity, selectivity, stability, and resistance to poisoning. Finally, a brief review of encapsulated catalysis in applying environmental catalysis, such as selective catalytic reduction for NOx removal, the degradation of VOCs, and advanced oxidation processes (AOPs) for environmental remediation, and its prospects and perspective are presented. We hope that this review will help reader better understand the influence of confinement effect on catalytic performance and provide some reference for the design of efficient catalysts. Nanoparticles encapsulated in nano-shells, nanopores, and two-dimensional intercalation are described in detail. Meanwhile, it clarifies how the confinement effect affects the catalytic performance and extends to applications in environmental catalysis, allowing us to design a confinement catalyst with the desired structure and properties. [Display omitted] •Strategies for encapsulating nanoparticles in 2D or 3D materials are summarized.•The confinement effect is discussed based on the catalyst performance.•The benefits of confined catalysts in NH3-SCR and the removal of VOCs are described.