Hysteretic Adsorption and Desorption of Hydrogen by Nanoporous Metal-Organic Frameworks

Abstract

Adsorption and desorption of hydrogen from nanoporous materials, such as activated carbon, is usually fully reversible. We have prepared nanoporous metal-organic framework materials with flexible linkers in which the pore openings, as characterized in the static structures, appear to be too small to allow H2 to pass. We observe hysteresis in their adsorption and desorption kinetics above the supercritical temperature of H2 that reflects the dynamical opening of the "windows" between pores. This behavior would allow H2 to be adsorbed at high pressures but stored at lower pressures.

Coordination Polymers and Metal Organic Frameworks Derived from 1,2,4-Triazole Amino Acid Linkers

“…It is possible that, after the initial H 2(g) sorption where the increasing pressure flexes-out the network to open the 'gate' to accommodate the guest, it keeps the network under stress and the subsequent desorption probably partially collapses the network while shrinking back. The retention of almost half of the adsorbed gas (3 cm 3 /g) in second or third run after depressurization at low temperature although less, is interesting and such retentions are significant in systems which show high sorption-desorption property [103]. Square shaped openings (Figure 8(b)) discovered on the cubic crystal surface of 4 stimulated us to investigate the 'porosity partitioning' by Hg porosimetry [104,105].…”

Facile Syntheses of Metal-organic Framework Cu3(BTC)2(H2O)3under Ultrasound

“…[1][2][3][4][5][6][7][8] The major applications currently being considered for these compounds involve gas storage, [9][10][11][12] catalysis, [13][14][15][16][17][18] separations, [19][20][21][22][23][24] as carriers for nano-materials 25,26 and drug delivery, 27,28 etc. For these applications, their high surface areas and unique pore structures are likely to offer many potential advantages over existing compounds.…”

Lithium‐Doped 3D Covalent Organic Frameworks: High‐Capacity Hydrogen Storage Materials

“…[2] Some MOFs, for example MOF-177 and MOF-5, have high BET specific surface areas (SSAs), and the strong London dispersion between linkers and connectors with hydrogen makes them attractive materials for hydrogen adsorption and storage. [3,4] However, MOFs still behave poorly at room temperature and cannot reach the target for practical use.…”