Increasing nuclearity of secondary building units in porous cobalt(II) metal-organic frameworks: variation in structure and H2 adsorption.
Reaction of Co(NO(3))(2)·6H(2)O with H(2)L [H(2)L = pyridine-4-(phenyl-3',5'-dicarboxylic acid)] under different reaction conditions gives three closely-related metal-organic framework polymers, {[Co(2)(L)(2)(DMF)]·n(solv)}(∞) (1), {[Co(L)]·2DMF}(∞) (2) and {[Co(3)(L)(3)(DMF)(0.5)(H(2)O)(1.5)]·n(solv)}(∞) (3). Variation in reaction conditions thus has a decisive impact on the materials isolated, producing frameworks based upon either binuclear (1, 2) or trinuclear (3) cobalt cluster nodes. Analysis of their crystal structures shows that all three contain considerable solvent-accessible volumes, an indication of porosity that is confirmed for desolvated 1 and 3, which can store up to 2.75 and 2.33 wt% of H(2) at 78 K and 20 bar, respectively.
School of Chemistry, University of Nottingham, University Park, UK NG7 2RD.
Junhua
J
Jia
Harprit Singh
HS
Athwal
Alexander J
AJ
Blake
Neil R
NR
Champness
Peter
P
Hubberstey
Martin
M
Schröder