Water sorption studies with mesoporous multivariate monoliths based on UiO-66
Hierarchical linker thermolysis has been used to enhance the porosity of monolithic UiO-66-based metal-organic frameworks (MOFs) containing 30 wt% 2-aminoterephthalic acid (BDC-NH2) linker. In this multivariate (i.e. mixed-linker) MOF, the thermolabile BDC-NH2 linker decomposed at ∼350 °C, inducing mesopore formation. The nitrogen sorption of these monolithic MOFs was probed, and an increase in gas uptake of more than 200 cm3 g−1 was observed after activation by heating, together with an increase in pore volume and mean pore width, indicating the creation of mesopores. Water sorption studies were conducted on these monoliths to explore their performance in that context. Before heating, monoUiO-66-NH2-30%-B showed maximum water vapour uptake of 61.0 wt%, which exceeded that reported for either parent monolith, while the highly mesoporous monolith (monoUiO-66-NH2-30%-A) had a lower maximum water vapour uptake of 36.2 wt%. This work extends the idea of hierarchical linker thermolysis, which has been applied to powder MOFs, to monolithic MOFs for the first time and supports the theory that it can enhance pore sizes in these materials. It also demonstrates the importance of hydrophilic functional groups (in this case, NH2) for improving water uptake in materials.
Funding
Nanoengineering and Processing of Metal-Organic Framework Composites for Photonic Sensors
European Research Council
Find out more...Transmission Electron Microscopy: Essential Support for Materials Synthesis
Engineering and Physical Sciences Research Council
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Publication
Materials Advances, 2024, 5, pp. 7679-7689Publisher
Royal Society of ChemistryOther Funding information
The authors thank the Royal Society (FCG\R1\201021) and the African Academy of Sciences for funding this project. The authors also thank the Crystal Engineering Group at the University of Limerick for providing the DVS instruments. J. C. T. and M. T. thank the European Research Council (ERC) Consolidator Grant PROMOFS (grant agreement 771575). L. G. M is grateful for the financial assistance she received from the European Union (grant no. DCI-PANAF/2020/420-028), through the African Research Initiative for Scientific Excellence (ARISE), pilot programme. The UK EPSRC is thanked for supporting electron microscopy at Cambridge (EP/P030467/1).Also affiliated with
- Bernal Institute
Sustainable development goals
- (3) Good Health and Well-being
- (6) Clean Water and Sanitation
- (13) Climate Action
External identifier
Department or School
- Chemical Sciences