In Situ FTIR Spectroscopy for Scanning Accessible Active Sites in Defect-Engineered UiO-66.

ABSTRACT: Three UiO-66 samples were prepared by solvothermal synthesis using the defect engineering approach with benzoic acid as a modulator. They were characterized by different techniques and their acidic properties were assessed by FTIR spectroscopy of adsorbed CO and CD₃CN. All samples evacuated at room temperature contained bridging μ₃-OH groups that interacted with both probe molecules. Evacuation at 250 °C leads to the dehydroxylation and disappearance of the μ₃-OH groups. Modulator-free synthesis resulted in a material with open Zr sites. They were detected by low-temperature CO adsorption on a sample evacuated at 200 °C and by CD₃CN even on a sample evacuated at RT. However, these sites were lacking in the two samples obtained with a modulator. I

SUBMITTER: Butova VV 

PROVIDER: S-EPMC10222444 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature