Tuning porosity in macroscopic monolithic metal-organic frameworks for exceptional natural gas storage
Widespread access to greener energy is required in order to mitigate the effects of climate change. A significant barrier to cleaner natural gas usage lies in the safety/efficiency limitations of storage technology. Despite highly porous metal-organic frameworks (MOFs) demonstrating record-breaking gas-storage capacities, their conventionally powdered morphology renders them non-viable. Traditional powder shaping utilising high pressure or chemical binders collapses porosity or creates low-density structures with reduced volumetric adsorption capacity. Here, we report the engineering of one of the most stable MOFs, Zr-UiO-66, without applying pressure or binders. The process yields centimetre-sized monoliths, displaying high microporosity and bulk density. We report the inclusion of variable, narrow mesopore volumes to the monoliths' macrostructure and use this to optimise the pore-size distribution for gas uptake. The optimised mixed meso/microporous monoliths demonstrate Type II adsorption isotherms to achieve benchmark volumetric working capacities for methane and carbon dioxide. This represents a critical advance in the design of air-stable, conformed MOFs for commercial gas storage. ; This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (NanoMOFdeli), ERC-2016-COG 726380. D.F.-J. thanks the Royal Society for funding through a University Research Fellowship. B.M.C. thanks the Ernest Oppenheimer Fund (Cambridge). J.S.A. would like to acknowledge financial support from MINECO (MAT2016–80285-p), GV (PROMETEOII/2014/004) and H2020 (MSCA-RISE-2016/NanoMed Project). J.G.L. acknowledges GV (GRISOLIAP/2016/089) for a research contract. J.P.M. would like to thank CRUK and The Cambridge Cancer Centre. P.Z.M. is grateful for start-up funds from the University of Sheffield. D.C.L. acknowledges the financial support of the Deutsche Forschungsgemeinschaft (DFG) through the collaborative research centre SFB1032 (Project B3) and ...
