Zinc paddlewheel metal-organic frameworks (MOFs) frequently exhibit low stability or complete collapse upon the removal of axial ligands. Hence, there are very few reports on gas adsorption of zinc paddlewheel MOFs. In this work, the N-2 and H-2 adsorption measurements were carried out for a zinc MOF (namely, SDU-1) based on two types of paddlewheel secondary building units (SBUs): [Zn-2(COO)(3)] and [Zn-2(COO)(4)]. Because of the existence of inherent surface instability upon removal of solvates in zinc paddlewheel SBU, SDU-1 possesses a very low surface area. Through metal-ion metathesis in a single-crystal-to-single-crystal fashion, the Zn2+ ions in SDU-1 were exchanged by Cu2+ ions to generate Cu-SDU-1. Through the measurements of gas adsorption and catalytic test, the porosity and catalytic capacity of Cu-SDU-1 have been improved significantly, compared to SDU-1.