Synthesis and characterization of (TBAPW11O39) hybrid Keggin type catalyst

Abstract

Polyoxometalate(POM) possesses unique characteristics that accommodate current society's material, health, environmental, energy, and technology demands. A hybrid organic-inorganic polyoxotungstate [TBAPW11O39] synthesized by the method which quaternary ammonium is introduced to a Keggin structure of polyoxometalate by metathetical organic cation exchange by adding tetrabutylammonium bromide (TBABr) to the solution of sodium salts in a heteropolyanion. The synthesized hybrid is characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM) with an Energy-dispersive X-ray spectroscope (EDS), thermogravimetric analysis (TGA), and Atomic force microscopy (AFM). The FTIR of [TBAPW11O39] matched the vibration patterns of FTIR of keggin structure type with a slight difference in absorption peaks between the IR spectra of sample and theoretical may relate to cationic structures. The principal characteristic peaks of XRD found in the region of 7–10°, 16–22°and 25–34°, with the highest peak in the first range: 7–10° that is a characteristic of the Keggin type. In addition, the nanostructure may confirm by XRD and FESEM analysis. The TGA shows the mass loss of [TBAPW11O39] in three steps and mainly at 400°C. The AFM of [TBAPW11O39] refers to small nanoparticles with an average size of 64.41 nm.