SYNTHESIS AND CHARACTERIZATION OF A NOVEL MICROPOROUS INDIUMPHOSPHATE

A microporous indiumphosphate has been synthesized for the first time from the hydrothermal reaction of H3PO4, In2O3 and H2O in the presence of one of the following templates, triethylamine (Et(3)N), n-butylamine (n-BuA), dimethylamine (DMA), dipropylamine (DPA), ethylenediamine (EDA), or tetramethylammonium hydroxide (TMAOH). Single crystal x-ray diffraction structural analysis demonstrates that the crystal crystallizes in orthorhombic symmetry, space group Pbca. One asymmetric unit consists of InPO4(H2O)(2) in composition. The 3D microporous structure contains 6- and 4-ring un-intersected parallel channels running along the b-axis. In and P atoms appear in a strict alternative order bridged through O atoms forming the octahedral and tetrahedral geometry respectively. Among the six O ligands of the In, four are framework O atoms and the other two are water oxygens. The P atoms are exclusively coordinated to framework O atoms. XRD, FT-IR and TG studies demonstrate that the microporous indiumphosphate is unstable to thermal treatment above 330 degrees C which is believed to be the consequence of removal of structural water molecules.