Impact of Hydrochloric Acid on Phase Formation of Titanium Dioxide Nanoparticles

Abstract

Titanium dioxide (TiO₂), one of the most fundamental nanomaterial had found numerous applications in our daily life due to it’s efficient photoactivity properties with relatively low cost and low toxicity. For instance, the photocatalytic environmental applications have been widespread from clean up and remediation, air, water and wastewater purification, hazardous waste control, to water disinfection. TiO₂ in nanoscale is preferred for all these applications to attain a remarkable improvement in its physical, chemical and electrical properties since the particle size, surface area, crystal structure, morphology, porosity and phase strongly influences the activity of the nanoparticles. In this paper, the impact of varying volume of hydrochloric acid on the phase formation while synthesis of nano TiO₂ by hydrolysis method has been studied in view of its applications for the photocatalytic reduction of carbon dioxide to methanol. Rutile-anatase composite of TiO₂ nanoparticles has been successfully synthesized by hydrolysis of titanium tetrachloride in hydrochloric acid. One mL of pure titanium tetrachloride was added dropwise to 1 mol dm⁻³ of the hydrochloric acid solution with varying volume that range from 50 to 200 mL was used. It occurs that yield of titanium dioxide decreases with the increase in the volume of the hydrochloric acid. X-Ray Diffraction (XRD) and Field Emission Scanning Electron Microscopic (FESEM) analysis were used for the structural and morphological characterization of the synthesized nano TiO₂ particles. XRD results indicate that the rutile phase diminished with the increase in the volume of sample. It was observed through FESEM analysis that particle size ranges from 20 nm to 90 nm, and it increased with increasing volume of sample. The knowledge of the impact of processing parameters on phase formation of TiO₂ nanoparticles during synthesis could be implied further for the conversion of carbon dioxide to methanol.