Isostructural nano Zn(II)-based metal–organic frameworks (MOFs), Zn-TMU, has been synthesized by ultrasound process and solvent-assisted linker exchange (SALE). Zn(II)-MOFs were investigated as CO2 capture compounds. Compared with ultrasound process, the as-prepared daughter frameworks showed enhanced CO2 sorption capacity, ascribed to the existence of structural defects during the SALE method. This study demonstrated that the gas storage depends mainly on the quality and defects in the structure, which depends on the synthetic conditions. This study is a new report of increasing CO2 sorption in Zn-TMU by a SALE method.