Green Synthesis Of Titania (TiO2) Nanoparticles From Bulk Titania Using Neem And Tumeric Extract As Capping Agents And Their Applications For The Colorimetric Detection Of Metal Ions

This work reports the synthesis of titania nanoparticles by green synthesis method using bulk titania dissolved in nitric acid or water with turmeric or neem leaf extract as capping agents. It is a simple and cost effective method. The nanoparticles were characterized using the powder-X-ray diffraction (p-XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX) and Fourier Transformed Infrared Spectroscopy (FTIR). The p-XRD pattern showed that titania nanoparticles of tetragonal rutile phase were obtained in all cases. The SEM showed spherical morphology and the particle sizes were calculated to be 75 nm and 113 nm (for the turmeric capped titania nanoparticles prepared by dissolving bulk titania in distilled water or nitric acid) while 124  nm and 97 nm were obtained for the neem capped titania nanoparticles prepared by dissolving bulk titania in distilled water or nitric acid respectively. The titania nanoparticles were used for the colorimetric detection of metals in aqueous solutions by depositing the nanoparticles on the filter paper by the doctor blading technique. Co 2+ was detected using the turmeric capped titania nanoparticles. Keywords : titania nanoparticles, colorimetric detection, green method, colloidal synthesis, spherical morphology, nano-modified filter paper