Pt-Based Nanoreactors Derived from ZIF-67 Nanocubes on Al₂O₃ Films for Low-Temperature CO Oxidation

Abstract

In the field of catalysis, nanoreactors with spatially restricted effects play a critical role to enhance the production efficiency of a variety of reactions. In this contribution, we used ZIF-67 nanocubes (size of 140 nm) as a template and conformally deposited Al 2 O 3 thin films by the atomic layer deposition (ALD) technique, wherein Pt nanoparticles (Pt NPs) as active sites were loaded on either the inside or outside of the Al 2 O 3 films. Notably, it was found that the water treatment of the nanoreactors was critical to the enhanced catalytic CO oxidation performance with substantially decreased T 100 (temperature to achieve 100% conversion). Various characterization results indicated the successful synthesis of yolk−shell structured ZIF-67/Pt@ 10Al 2 O 3 -W catalyst with excellent CO oxidation activity and good long-term stability. In addition, in situ diffuse reflectance infrared Fourier transform spectroscopy was used to explore the catalytic oxidation process, and the results revealed that the reason for the superior CO catalytic activity of the designed nanoreactors was ascribed to the moderate CO surface coverage provided by the Al 2 O 3 films and the activated oxygen species. In summary, this work provides some insights into the preparation of metal− organic framework-based nanoreactors using ALD-assisted methods.

Graphitic Carbon Nitride Composites with Gold and ZIF-67 Nanoparticles as Visible-Light-Promoted Catalysts for CO2 Conversion and Bisphenol A Degradation

“…However, as the amount of ZIF-67 coupled increased, the • OH-related fluorescence intensity became much stronger, especially in the case of the 3ZIF/1.5Au-PCN sample. However, if an excess amount of ZIF was used, the amount of • OH produced declined because of the inhibited optimal amount …”

“…However, if an excess amount of ZIF was used, the amount of • OH produced declined because of the inhibited optimal amount. 40 In the case of the photocatalytic activities, it can be observed that the activities of 1.5Au-PCN efficiently improved after coupling of ZIF-67. Compared to pristine 1.5Au-PCN, the YZIF/1.5Au-PCN nanocomposites have improved the photocatalytic activities for conversion of CO 2 (Figure 10A) and BPA decontamination (Figure 10B).…”

Periodic arrays of structurally complex oxide nanoshells and their use as substrate-confined nanoreactors

“…23 With metal nanostructures being highly susceptible to morphological transformations at elevated temperatures, ALD-deposited oxides have also proven effective in impeding the surface diffusion pathways responsible for these changes. In this role, they have preserved the shape-dependent properties of nanometals, 12,24,25 inhibited nanoparticle sintering, 17,18,[26][27][28][29] and allowed for improvements to nanostructure crystallinity. 30 This has allowed for the use of these materials in high-temperature applications related to catalysis 11 and refractory plasmonics.…”