Microstructural characteristics of boron doped TiO2 nanocrystals

• Main Authors: Jayadevan, K. P., Kerkar, Shubhada S.
• Format: Conference Proceeding
• Language: English
• Subjects: Agglomerates; Boron; Crystallites; Crystallization; Density functional theory; Morphology; Nanocrystals; Optimization; Pictures; Rutile; Scanning electron microscopy; Sol-gel processes; Titanium dioxide
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/1.5130221

Undoped and boron doped(∼1, 2 and 4 wt.% boron) nanocrystalline rutile TiO2 have been prepared through a conventional sol-gel process using hydrolysis reaction of titanium isopropoxide and boric acid as reactants in alcoholic medium. X-ray diffraction (XRD) study of 800°C calcined powder of undoped TiO2 shows peaks corresponding to rutile TiO2 with average crystallite size of ∼60 nm. When TiO2 is doped with boron, the average crystallite size decreases and it is ∼30 nm. Scanning electron microscopic (SEM) examination of surface morphology indicates that the undoped rutile shows well crystallized growth morphology. Upon boron doping, the crystal facets are smooth and show a reduction in agglomerate size up to a small amount of 1 and 2 wt.% of boron. For 4 wt.%boron doped TiO2, large island-like agglomerates are observed in SEM pictures, whereas crystallite size remains close to ∼30 nm. Energy dispersive X-ray (EDX) spectra of boron doped TiO2 samples do not show any appreciable detection level for boron, whereas EDX composition analysis indicates the presence of oxygen vacancies. Density-functional theory (DFT)-based computationalstudy of structural optimization of boron doped TiO2 supercell shows interstitial site as favorable position for boron.