Structural diversity and luminescent sensing of metal-organic frameworks with 2,6-Di(1H-imidazol-1-yl) naphthalene ligands

Abstract

Reactions of ligands 2,6-Di(1H-imidazol-1-yl) Naphthalene (L) and corresponding metal salts under hydrothermal conditions gave rise to a new Metal-Organic Framework (MOF), namely Cd(L)(CNN)·3H2O (1). (H2CNN = 4-(4-Carboxy-2-Nitrobenzene)-3-Nitrobenzoic acid). The crystal structure was characterized by Powder X-ray diffraction (PXRD), thermogravimetric analyses (TGA), infrared spectra (IR), and elemental analyses (EA). 1 belongs to orthorhombic system, space group Pbcn, with a = 18.41(5) nm, b = 12.72(4) nm, c = 27.42(7) nm, V = 6421(3) nm3, Dc = 1.44 mg/m3, Z = 4, F (0 0 0) = 2792, GOF = 0.94, R1 = 0.06, wR2 = 0.15. This MOF has a three-dimensional (3D) penetration structure. Furthermore, the thermal stability and photoluminescence property of the MOF was investigated. Meanwhile, the thermal stability and luminescence properties of the crystal were tested. It was found that 1 is a highly efficient luminescent probe sensor for the identification and determination of Fe3+ cations, Cr2O72− and CrO42− anions, acetone organic small molecules, and antibiotics.