Improving the Removal Efficiency of Oxygenated Volatile Organic Compounds by Defective UiO-66 Regulated with Water

The purification of oxygenated volatile organic compounds VOCs (OVOCs), important precursors of ozone and particulate matters, has triggered intensive research interests. UiO-66 with high photocatalytic activity have shown great potential. However, the lack of active sites severely limited the trapping and degradation of OVOCs. Herein, reo-UiO-66 with increased specific surface area, hierarchical porous structure and tunable acidic/basic sites was synthesized by simply adding water as the modulator. XRD, TGA and FTIR results confirmed the formation of reo-defects, which significantly affected the surface hydrophilicity and active sites of UiO-66. The adsorption of Lewis acidic acetaldehyde was enhanced by 265 times with coordinative unsaturated Zr acting as the dominant adsorption sites. The degradation efficiency of typical OVOCs (acetaldehyde and acetone) increased from 0% and 25% to 50% and 73%, respectively. This work provided a facile method to modulate the micro-environment in MOFs for the efficient capture and catalytic purification of OVOCs. Environmental Implication Oxygenated volatile organic compounds (OVOCs) are irritating and carcinogenic, as well as the main contributors to ozone production. As representatives of OVOCs, the removal of acetaldehyde and acetone is important for atmospheric control and indoor air purification. OVOCs are characterized by dynamic flow, so how to effectively capture and remove them is the focus of research. In this study, the adsorption and degradation efficiency of the samples for OVOCs was improved by introducing defects. Compared with previous studies on acetaldehyde degradation by MOFs, the experimental conditions are closer to real life, which provides the possibility of practical application.