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A rapid and simple analytical approach is developed to screen the semiconducting properties of metal organic frameworks (MOFs) by modeling the band structure and predicting the density of state of isoreticular MOFs (IRMOFs). One can consider the periodic arrangement of metal nodes linked by organic subunits as a 1D periodic array crystal model, which can be aligned with any unit-cell axis included in the IRMOF's primitive cubic lattice. In such a structure, each valence electron of a metal atom feels the potential field of the entire periodic array. We allocate the 1D periodic array in a crystal unit cell to three IRMOFs-n (n = 1, 8, and 10) of the Zn 4 O(L) 3 IRMOF series and apply the model to their crystal lattices with unit-cell constants a = 25.66, 30.09, and 34.28 Å, respectively. By solving Schrodinger's equation with a Kronig−Penney periodic potential and fitting the computed energy spectra to IRMOFs' experimental spectroscopic data, we model electronic band structures and obtain densities of state. The band diagram of each IRMOF reveals the nature of its electronic structures and density of state, allowing one to identify its n-or p-type semiconducting behavior. This novel analytical approach serves as a predictive and rapid screening tool to search the MOF database to identify potential semiconducting MOFs.

Bioinspired porous microstructures of iron-tannate (Fe(III)-TA) coordination polymer framework were synthesized by catenating natural tannic acid with iron(II), using a scalable aqueous synthesis method in ambient conditions. The chemical composition, morphology, physiochemical properties, and colloidal stability of microstructures were elucidated. The surface area (SBET) and the desorption pore volume were measured to be 70.47 m2/g and 0. 44 cm3/g, respectively, and the porous structure was confirmed with an average pore dimension of ~27 nm. Microstructures were thermally stable up to 180 °C, with an initial weight loss of 13.7% at 180 °C. They exhibited high chemical stability with pH-responsive amphoteric properties in aqueous media at pH levels ranging from 2 to 12. Supporting their amphoteric sorption, microstructures exhibited rapid removal of Pb+2 from water, with 99% removal efficiency, yielding a maximum sorption capacity of 166.66 mg/g. Amphoteric microstructures of bioinspired metal–phenolate coordination polymers remain largely unexplored. Additionally, natural polyphenols have seldomly been used as polytopic linkers to construct both porous and pH-responsive amphoteric coordination polymer frameworks with a robust structure in both acidic and basic media. Thus, this de novo porous microstructure of Fe(III)-TA and its physiochemical surface properties have opened new avenues to design thermally and chemically stable, eco-friendly, low-cost amphoteric sorbents with multifunctionality for adsorption, ion exchange, separation, storage, and sensing of both anions and cations present in heterogeneous media.

A base-catalyzed sol–gel approach combined with a solvent-driven self-assembly process at low temperature is augmented to make highly mesoporous metal oxide nanostructures of manganese and copper, and hydroxide nanostructures of magnesium.

The unique and highly organized three-dimensional structure of metal−organic frameworks (MOFs) formed by selfassembled organic chromophores with metal ions emerges as nextgeneration luminophores for optoelectronic devices. Herein, for the first time, we have investigated the photophysics of selfassembled Mn(II)-MOF microstructures, consisting 2,6-naphthalenedicarboxylic acid (NDC), as a blue luminophore. The crystalline octahedral structure of Mn-MOF with a rigid framework of NDC units exhibits solvent-driven charge transfer dynamics, inducing either chromophore-localized luminescence or ligand-tometal charge transfer luminescence in solution phase, while only the ligand-centered luminescence is observed in thin films. The excited-state emission lifetime decay experiments of Mn-MOF reveal the exciton behavior of the ligand, which corresponds to chromophore's S 1 →S 0 emission within the MOF framework. The excited-state fluorescence lifetime decay profile of NDC within the MOF structure exhibits a shorter exciton lifetime, which is 5.58 ns, compared to the excited-state emissive lifetime of the linker alone, evidencing the dependency of the chromophore emission by the topology of the Mn-MOF three-dimensional structure. The rigidity and interpenetrated arrangement of NDC chromophores may contribute to the shorter excited-state emissive lifetime, evidencing that the ligand arrangement plays a key role in the photophysical properties of Mn-MOFs.