A flexible porous Cu(ii) bis-imidazolate framework with ultrahigh concentration of active sites for efficient and recyclable CO2 capture

By virtue of planar Cu2(μ-OH)2(2+) cluster units, a flexible porous metal azolate framework not only adsorbs large amounts of CO2 (19.6 wt% or 266 g L(-1) at 298 K and 1 atm) with a high zero-coverage adsorption enthalpy (-47 kJ mol(-1)), but also desorbs quickly at very low temperatures.