An investigation on effect of complexing agents on zirconium based ternary metal oxide nanoparticles by co-precipitation method

Abstract

Wet chemical synthesis of Zirconium Bismuth Molybdate (ZBM) nano-particles and influence of Triethanolamine (TEA) and Tri Sodium Citrate (TSC) on various physical properties are highlighted in this work. Zirconium oxychloride, bismuth nitrate and sodium molybdate are used as reagents. Structural, optical, morphological and thermal properties of as prepared materials are characterized by XRD, SEM-EDAX, HR-TEM, UV–Vis–NIR spectroscopy, Photoluminescence spectroscopy, FTIR spectroscopy and TGA-DTA. X-ray Diffraction pattern confirms the formation of poly-crystalline zirconium bismuth molybdate with monoclinic ZrO2 phase and orthorhombic γ-Bi2MoO6. Crystallite size of all the samples fall in the range 16.097–26.278 nm. All the samples have maximum absorption in the UV region. The indirect band gap energy calculated from DRS spectra revealed ZBM has wide band gap in the range 2.592–2.982 eV and also an interesting phenomenon of line broadening of absorbance peak is observed under the influence of complexing agents. Formation of ZBM is further confirmed by FTIR spectra and purity of samples are revealed from EDAX spectra. TGA-DTA data indicated that ZBM with TSC has more thermal stability. Activation energy for thermal degradation process of the samples are studied by Coat–Redfern method, by assuming first order kinetics. Which shows that sample treated with TSC has more activation energy as compared to other samples indicating high thermal stability. Three PL emission peaks, one broad peak at Indigo-Blue and the others at Green wavelength region on UV excitation is observed on each sample, among which peak around the Indigo-blue region has maximum intensity. Emission peak intensity is higher for the sample treated with TSC and slight changes in intensity and peak positions is observed on the addition of TEA and TSC. A Characteristic blue shift in the emission spectra is observed for each sample treated with complexing agents.