| Abstract
| - The effects of pore size on the hydrogen storage properties of a series of pillared layered solids based on theM(L)[M‘(CN)4] structural motif, where M = Co or Ni, L = pyrazine (pyz), 4,4‘-bipyridine (bpy), or 4,4‘-dipyridylacetylene (dpac), and M‘ = Ni, Pd, or Pt, has been investigated. The compounds all possess slitlikepores with constant in-plane dimensions and similar organic functionality. The pore heights vary as a functionof L and provide a means for a systematic investigation of the effects of pore dimension on hydrogen storageproperties in porous materials. Hydrogen isotherms were measured at 77 and 87 K up to a pressure of 1 atm.The pyz pillared materials with the smallest pore dimensions store hydrogen at a pore density similar to thatof liquid hydrogen. The adsorbed hydrogen density drops by a factor of 2 as the relative pore size is tripledin the dpac material. The decreased storage efficiency diminishes the expected gravimetric gain in capacityfor the larger pore materials. The heats of adsorption were found to range from 6 to 8 kJ/mol in the series andweakly correlate with pore size.
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