Inquiry for the multifunctional design of metal–organic frameworks: in situ equipping additional open metal sites (OMSs) inducing high CO2 capture/conversion abilities

On the basis of our conception for the in situ fabrication of multifunctional metal–organic frameworks (MOFs), a binuclear Co-MOF [Co3(μ2-OH)(bpydc)(Htpim)2]·3NO3−·4MeOH·5DMA (1) (H2bpydc = (2,2′-bipyridine)-5,5′-dicarboxylic acid, Htpim = 2,4,5-tri(4-pyridyl)imidazole, DMA = N,N-dimethylacetamide) with additional unsaturated open cobalt sites was blueprinted and accomplished. Compared to the parent structure, the co-existence of multifunctional sites (Lewis acid sites, Lewis basic sites and Bronsted acid sites) afforded a highly increased CO2 uptake of 110.5 cm3 g−1 at 273 K, together with the synergistic catalysis in promoting the CO2 cycloaddition reaction. Consequently, such an in situ micro-fine functional design offers the possibility of property-improvement/enrichment for the pristine network.