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Ionic tetrapodal ligands with colinear coordinating arms are very effective for designing hybrid porous materials with unusual structure and properties. The novelty of this research work lies in the utilization of a unique borate ligand that leads to charge-separated MOF structure with tailor designed properties. Borate ligands being tetrahedral afford 3D materials and the negative charge of borate anion can compensate the positive charge of metal ion in the framework. The borate ligands designed in this research consists of quaternary ammonium cation and anionic borate with four pyridine arms. These ligands upon coordination with Cu(I), Cu(II), Ag(I) and Co(II) metal cations formed six different charge-separated MOFs (UNM-1 to UNM-6). Chapter 1 covers a brief review on the design, synthesis, classification and applications of MOFs. Additionally, MOF interpenetration, control and applications of interpenetration are discussed with examples. Chapter 2 is about the synthesis, structural characterization and application of a charge-separated diamondoid UNM-1 MOF assembled from tetrakis(4-pyridyltetrafluorophenylethynyl)borate (T1) and Cu(I) metal cation. UNM-1 MOF structure displays 4-fold interpenetration, resulting in high environmental stability, and at the same time possesses relatively large surface area (SABET = 621 m2/g) due to the absence of free ions. Gas adsorption measurements revealed temperature-dependent CO2 adsorption/desorption hysteresis and large CO2/N2 ideal selectivities up to ca. 99 at 313 K and 1 bar, suggesting potential applications of this type of charge-separated MOFs in flue gas treatment and CO2 sequestration. In Chapter 3, synthesis and single-crystal structural characterization of four new charge-separated MOFs (UNM-2, UNM-3, UNM-4 and UNM-5) based on two tetrapodal borate ligands: (T1) and tetrakis(4