A new NbO-type metal-organic framework ZJNU-40 incorporating highly polarized benzothiadiazole moieties exhibits a high CO2 uptake of 108 cm(3) g(-1) at 296 K and 1 atm, as well as good adsorption selectivities of CO2 over CH4 and N2 at room temperature, which is superior to that of the analogous MOF NOTT-101.