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Supramolecular 3D Zn(II) coordination polymer {[Zn(bim)(bdc)]⋅0.8DMF⋅0.4EtOH⋅0.1H₂O }_n (<b>Zn-MOF</b>), constructed from Zn²⁺ ions, bis(imidazol-1-yl)methane (bim) and terephthalate (bdc²⁻) anions, was synthesized and structurally characterized. <b>Zn-MOF</b> crystallizes in the tetragonal crystal system, space group <i>P</i>4₂/<i>n</i>. Each Zn(II) ion coordinates two neutral bim molecules in a bridging bidentate coordination mode via nitrogen atoms at position 3 of the imidazole rings and two bdc²⁻ anions, with monodentate coordination of the carboxylate group for one of them and bidentate coordination for another. Zn(II) cations are in a distorted square pyramidal ZnN₂O₃ coordination environment. Metal cations are alternately linked by the bim and bdc²⁻ ligands, forming a two-dimensional layered structure along the crystallographic plane <i>ab</i>. As a result of layer interpenetration, a supramolecular 3D network is formed. <b>Zn-MOF</b> demonstrated blue (aquamarine) emission with a maximum at 430 nm upon excitation at 325 nm. The luminescence lifetime of 6 ns is characteristic for ligand-centered fluorescence. The luminescent sensing properties of <b>Zn-MOF</b> in ethanol suspension toward inorganic cations and anions were evaluated and an emission quenching response was observed for Fe³⁺ and chromate/dichromate ions. Photoinduced electron transfer from <b>Zn-MOF</b> to Fe³⁺ was elucidated as a possible quenching mechanism on the basis of DFT calculations.