Shape Controlled Synthesis of Barium Carbonate Microclusters and Nanocrystallites using Natural Polysachharide – Gum Acacia

Abstract

Different morphosynthesis strategies for BaCO<SUB>3 </SUB>using natural polysaccharide-gum acacia (GA) as templating species are presented. The influence of GA with different functionalities such as –OH, –COOH and -NH<SUB>2</SUB> on the crystallization and structure formation was investigated. Some interesting morphologies, including rods, dumbbell, double-dumbbell and flower like clusters, can be readily generated by using GA as cooperative modifier in the mineralization process, under the conditions of 0.5%, 1% of templating species and at ambient temperature. The modifier GA and its concentration is the key factor in this system. In continuation, morphology was also examined for mixed metal carbonates (Ba-LaCO<SUB>3</SUB>, Ba-TbCO<SUB>3</SUB>). The possible formation mechanism of the nanocrystallites is discussed. Structural characterization of the synthesized materials was investigated byPowder X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Analysis (EDAX), Transmission Electron Microscopy (TEM), Thermogravimetric analysis (TGA) coupled Mass (MS) and Fourier Transform Infrared spectroscopy (FT-IR).