Band Gap Modulation in Zirconium-Based Metal-Organic Frameworks by Defect Engineering

25 July 2019, Version 2
This content is a preprint and has not undergone peer review at the time of posting.

Abstract

We report a defect-engineering approach to modulate the band gap of zirconium-based metal-organic framework UiO-66, enabled by grafting of a range of amino-functionalised benzoic acids at defective sites. Defect engineered MOFs were obtained by both post-synthetic exchange and modulated synthesis, featuring band gap in the 4.1-3.3 eV range. Ab-initio calculations suggest that shrinking of the band gap is mainly due to an upward shift of the valence band energy, as a result of the presence of light-absorbing monocarboxylates. The photocatalytic properties of defect-engineered MOFs towards CO2 reduction to CO in the gas phase and degradation of Rhodamine B in water were tested, observing improved activity in both cases, in comparison to a defective UiO-66 bearing formic acid as the defect-compensating species.

Keywords

Metal-Organic Frameworks
zirconium
defects
Defect engineering
Photocatalysis Enhancement
Density Functional Theory calculations

Supplementary materials

Title
Description
Actions
Title
ESI Taddei Rev ChemRxiv
Description
Actions

Comments

Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.