Hydrothermal synthesis and characterization of two novel inorganic-organic hybrid materials

By using different organic ligands, two 3D inorganic-organic hybrid compounds Co(C4H4N2)(VO3)2 1 and Co(C12H12N2)(VO3)2 2 were synthesized by hydrothermal reaction and characterized by X-ray crystallography. Crystal data: 1. crystal system orthorhombic, space group Pnna, a=10.188(2), b=11.497(2), c=7.3975(15), V=866.5(3)3, Z=4, Dcalcd= 2.705 g/cm3; 2. crystal system triclinic, space group P1– (No. 2), a=8.3190(17), b=8.4764(17), c=11.183(2), α=95.48(3)°, β=92.03(3)°, γ=107.24(3)°, V=748.0(3)3, Z=2, Dcalcd=1.958 g/cm3. The framework of compound 1 contains both {Co(C4H4N2)} and infinite metavanadate chains. Crystal structure of compound 2 is constructed with inorganic {CoV2O6} layers across-linked by organic 1,2-bis(4-pyridyl) ethane ligands. The two compounds are thermally stable to approximately 410 °C and 350 °C, respec- tively. Their optical band gaps are determined to be 2.13 eV and 2.12 eV by UV-VIS-NIR diffuse reflectance spectra, which revealed their nature of semiconductor and optical absorption features.