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Metal-Organic Frameworks (MOFs) are porous coordination polymers formed by linking metal ions to a variety of ligands. These materials have applications in many fields, including gas storage, gas separation, catalysis, and sensors, due to their unique properties, such as porosity, high surface area, low density, stability and rigidity. Most reported MOFs contain neutral clusters with limited local electric fields, resulting weak interactions with the incoming guest molecules. However, some MOFs are ionic with isolated charges, either positive or negative, containing pore clogging counter ions that result in limited pore availability. Charge separated, or zwitterionic, MOFs are ionic MOFs containing positive and negative charges, separated at fixed distances, that possess favorable electrostatic interactions with the guest molecules. Herein, we report the synthesis, characterization and gas adsorption analysis of a zwitterionic diamondoid MOF prepared by coordinating an anionic borate ligand to a cationic Cu(I) metal. The resulting MOF was four-fold interpenetrated with a significantly larger BET surface area of 621 m2/g and high environmental stability due to the absence of free ions. At 313 K and under 1 bar pressure, the CO2 adsorption isotherm of this MOF displayed a temperature dependent adsorption/desorption hysteresis and CO2/N2 ideal selectivity of up to 99. The isosteric heat of CO2 adsorption at zero coverage was 15.85 KJ/mol, confirming the pure physical interaction of MOF during adsorption. The high CO2 uptake at 313 K, excellent environmental stability, and reasonable heat of adsorption makes this MOF a potential adsorbent for flue gas treatment in the future. [ABSTRACT FROM AUTHOR]