Etching of cubic Pd@Pt in UiO-66 to obtain nanocages for enhancing CO2 hydrogenation

• Published in: Materials today energy 2021-03, Vol.19, p.100585, Article 100585
• Main Authors: Li, Lishuang, Pan, Xinbo, Lan, Dengpeng, Xu, Haitao, Ge, Jianping, Zhang, Huaqian, Zheng, Zhizhong, Liu, Jichang, Xu, Zhenliang, Liu, Jinku
• Format: Article
• Language: English
• Subjects: Catalysis; Hollow metal; MOFs; Nanocubes; RWGS reaction
• ISSN: 2468-6069; 2468-6069
• DOI: 10.1016/j.mtener.2020.100585

In this study, the Zr-based metal-organic framework (MOF) catalysts Pd@UiO-66, Pd@PtNPs@UiO-66, and Pd@PtNCs@UiO-66, were assembled. Core-shell Pd@Pt nanoparticles (NPs), in which cubic Pd NPs serve as the core for the epitaxial growth of Pt shells, were encapsulated into UiO-66 to obtain Pd@PtNPs@UiO-66, which were subjected to further etching to obtain Pd@Pt nanocages (NCs) in UiO-66. CO2 conversion and CO selectivity in reverse water-gas shift reaction with Pd@PtNCs@UiO-66, Pd@PtNPs@UiO-66, and Pd@UiO-66 were 19.6% and 72.3%, 16.2% and 85.9%, and 15.6% and 52.3%, respectively. This proves that the cubic Pd@PtNCs can enhance the CO2 hydrogenation and long-term stability. M@UiO-66 nanocomposite catalysts are prepared by in situ encapsulation of nanoparticles in advance into the core of a metal-organic framework (MOF), which combines the high catalytic activity of nanoparticles with the porous and stable properties of MOFs. The synergy between metal nanoparticles and the MOF greatly improves the utilization efficiency of the catalyst in reverse water-gas shift. [Display omitted] •A hollow core-shell Pt-based nanocage catalyst embedded in UiO-66 is synthesized for CO2 hydrogenation.•CO2 conversion and CO selectivity in reverse water-gas shift are as high as 22.6% and 78.2%, respectively.•A novel postetching method for hollow core-shell nanocomposite is proposed.