Tuning porosity in macroscopic monolithic metal-organic frameworks for exceptional natural gas storage

Abstract

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.

Understanding the multiscale self-assembly of metal–organic polyhedra towards functionally graded porous gels

“…pH, temperature, solvent, use of surfactants, or concentration of reagents). [22][23][24] However, the solution-phase techniques that are oen used to elucidate the molecular self-assembly mechanisms of gels, such as NMR, 25 rheology, 26 or light scattering, 27 are ineffective due to the low solubility of MOFs.…”

Redox Tuning in Crystalline and Electronic Structure of Bimetal–Organic Frameworks Derived Cobalt/Nickel Boride/Sulfide for Boosted Faradaic Capacitance

“…Recently, metal–organic frameworks (MOFs), which are self‐assembled by metal ions (or metal clusters) with organic ligands in high crystallinity and long‐range order, are considered as emerging porous materials for electrochemical energy storage applications . In sharp contrast to the inorganic electrode materials, their diverse topology structure, tunable porosity, and abundant metal ions allow them to be a promising energy storage material . However, the poor conductivity and lack of structural stability of pristine MOFs remain the critical limitations for practical applications in energy storage devices .…”

Water-based routes for synthesis of metal-organic frameworks: A review

“…There has been a substantial increase in interest of MOFs owing to their attractive physicochemical characteristics such as high surface area, permanent porosity, abundant active sites, and flexible chemical structure [4][5][6][7][8][9]. To date, the main focus of MOF investigations is the optimization of their structures or properties, such as increasing the crystallinity and pore size, to develop their potential applications in gas storage [10][11][12][13], adsorption and separation [14][15][16][17], large molecule encapsulation [18][19][20], supercapacitors [21][22][23], energy conversion [24,25], chemical sensors [26][27][28], biomedicine [29,30], and catalysis [31][32][33]. However, the synthesis conditions of MOFs for eco-friendly and industrial scale-up were only sparsely investigated in both research and industrial laboratories [34,35].…”