Novel sonochemical green approach for synthesis of highly crystalline and thermally stable barium sulphate nanoparticles using Azadirachta indica leaf extract

Abstract

Nanomaterial synthesized using plant extract is a viable and better alternative to chemical synthesis methods. A simple, nontoxic and inexpensive strategy, which meets the standard of green chemistry, has been introduced for the synthesis of highly crystalline and thermally stable barium sulphate (BaSO4) nanoparticles. Thiswork reports ultrasonic-assisted green synthesis of BaSO4 nanoparticles using Azadirachta indica leaf extract at room temperature. The as-synthesized BaSO4 nanoparticles were subjected to various physiochemical characterization using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission gun-scanning electron microscopy (FEG-SEM), thermogravimetric analysis (TGA) and energy-dispersive X-ray spectroscopy (EDX). XRD explored orthorhombic, highly crystalline and pure BaSO4 (JCPDS: 24-1035) with average crystallite size of 55.6 nm. FEG-SEM study revealed about size (>80 nm) of BaSO4 nanoparticles. Co-precipitation method was also employed to synthesize BaSO4 for comparison between biogenic and chemical methods. The size of BaSO4 nanoparticles obtained using co-precipitation method was very large with rod shape morphology. Novel sonochemical green method is preferable because of its control over particle size as well as morphology. FTIR study confirmed the formation of BaSO4 nanoparticles. High thermal tolerance and stability of BaSO4 nanoparticles was evidenced from single step weight loss in TGA. In addition, strong characteristic signals of barium, sulphur and oxygen in EDX confirmed the purity of ultrasonic-assisted green synthesized BaSO4 nanoparticles. Overall, this one pot, inexpensive and green sonochemical approach is a promising method for the synthesis of BaSO4 nanoparticles, which might be used for various commercial applications.