International Journal of Emerging Technology and Advanced Engineering Website: www.ijetae.com (ISSN 2250-2459, ISO 9001:2008 Certified Journal, Volume 3, Issue 1, January 2013) Preparation and Characterization of Nanosized Tio2 Powder by Sol-Gel Precipitation Route Kavitha Thangavelu 1, Rajendran Annamalai2, Durairajan Arulnandhi3 1 3 Research Scholar, 2Professor, Department of Physics, Nehru Memorial College, Tiruchirapalli, Tamilnadu, India. UG Scholar, Department of Mechanical Engineering, K.S.R. College of Engineering, Tiruchengode, Tamil Nadu, India. Abstract - In this work, the preparation of nano-sized TiO2 powder via sol-gel precipitation route by using hydrolysis of titanium tetraisopropoxide (Ti(OiPr)4) with ethanol and water mixture as titania source. The samples were characterized by XRD, SEM-EDAX, and FT-IR studies. Surface morphological studies obtained from SEM micrograph showed the particles with the spherical shapes are anatase in nature. The Crystalline size of TiO2 powder has obtained is ~6nm for anatase at 400 ºC by controlling the acidity. In FT-IR, all the peaks observed were around 460-560 cm-1 due to stretching and bending vibrations of -OH groups. II. EXPERIMENTAL SECTION Materials All reagents used were of analytical grade purity and were procured from Sigma Aldrich 97% Co. Ltd. India Synthesis of Nano Tio2 All the reagents used were of analytical grade and no further purification was done before use. TiO2 nanopowders were prepared via sol–gel method using titanium tetraisopropoxide (TTIP, sigma Aldrich), distilled water, and ethyl alcohol (EtOH, Merck) as the starting materials. The sol-gel synthesized TiO2 was obtained from Titanium tetraisopropoxide (Ti(OiPr)4) was dissolved in absolute ethanol and distilled water was added to the solution in terms of a molar ratio of TTIP: H2O=1:4. Nitric acid (HNO3) was used to adjust the pH and for restrain the hydrolysis process of the solution. The obtained solutions were kept under slow-speed constant stirring on a magnetic stirrer for 40 min at room temperature. In order to obtain nanoparticles, the gels were dried under 50oC for 1.5 hr to evaporate water and organic material to the maximum extent P. Chenga et al. [12]. After ball milling N. Babaei et al. [14] the dried powders obtained were calcinated at 400ºC for 2 h to carry out to obtain desired TiO2 nanocrystalline P. Chenga et al. [12]. The photographic view of portable ball miller as shown in the figure 2.1 and a process flow chart depicting the synthesis of nanocrystalline TiO2 is shown in figure 2.2. Keywords - TiO2 nanoparticles, Sol-gel route, Anatase, XRD, SEM. I. INTRODUCTION Titanium-di-oxide is one of the most attracted materials in nanoscience and nanotechnology because of having a lot of interesting properties from fundamental and practical point of view N. Castillo et al. [1]. Although many striking results have been achieved when using nano TiO2 in the photo catalytic degradation of contaminated compounds or in the photo electrochemical solar-cell fabrication, efforts of scientists to improve performances of this material continuously increase day by day Dirk Verhulst et al. [2]. Crystalline titania has three modification phases which are rutile (tetragonal), B. L. Bischof et al. [7] anatase (tetragonal) and brookite (orthorhombic) Pham Van Nho et al. [3]. Anatase-type TiO2 has excellent photocatalytic activity and widely used as catalysts for decomposition of a wide variety of organic and inorganic pollutants. Many methods have been established for titania synthesis such as sol-gel technique S. Mahshid et al. [4], hydrothermal method C.C Wang et al. [5], chemical vapor deposition H. Liu et al; Dongjin Byun et al. [6,9], direct oxidation and others [9]. Among them, the sol-gel technique is one of the most used methods due to its possibility of deriving unique metastable structure at low reaction temperatures and excellent chemical homogeinity Jinghuan Zhang et al. [8]. In this work, we report novel sol-gel method to synthesis nano sized TiO2 powder at room temperature and the obtained powder was analyzed for Grain size by XRD B.D. Cullity [10], Surface morphology by SEM, Chemical composition by EDAX and Metal oxide bonds by FTIR. Fig 2.1 The photographic view of Portable ball milling 636 International Journal of Emerging Technology and Advanced Engineering Website: www.ijetae.com (ISSN 2250-2459, ISO 9001:2008 Certified Journal, Volume 3, Issue 1, January 2013) 400 350 Intensity (a.u) 300 250 200 150 100 0 10 20 30 40 50 60 70 80 2ø (Degree) Fig 3.1 XRD patterns of titania particles calcined at 400°C Calcination is a common treatment used to improve the crystallinity of TiO2 powders Jinghuan Zhang et al. [8]. It can be obviously seen from fig.3.1 the phase transformation from amorphous to anatase occurred at about 400ºC. Crystallite size was obtained by DebyeScherrer’s formula given by equation Fig 2.2 Flow chart showing preparation of nano-TiO2 powders through a Sol-Gel process D=Kλ/ (βcosθ) Where D is the crystal size; λ is the wavelength of the Xray radiation (λ=0.15406 nm) for CuKα; K is usually taken as 0.89; and β is the line width at half-maximum height [10]. The crystallite size obtained using this formula is ~6 nm for sol-gel derived particles. Characterization The prepared Nano particles were characterized for the crystalline structure using D8 Advance X-ray diffraction meter B.D. Cullity et al. [10] (Bruker AXS, Germany) at room temperature, operating at 30 kV and 30 mA, using CuKα radiation (λ = 0.15406 nm). The crystal size was calculated by Scherrer’s formula. Surface morphology was studied by using SEM-EDAX (Model JSM 6390LV, JOEL, USA) and FTIR spectra were measured on an AVATAR 370-IR spectrometer (Thermo Nicolet, USA) with a wave number range of 4000 to 400 cm−1. SEM Morphology The morphology of calcinated titania powders at 400 ºC observed by SEM is shown in fig.3.2 (a). The pure TiO2 particles exhibited irregular morphology due to the agglomeration of primary particles and with an average diameter of ~6nm. III. RESULTS AND D ISCUSSIONS Calcination temperature The XRD patterns of the nanoparticles obtained by solgel route are shown in Fig. 3.1. XRD patterns of dried sample at 50 ºC were largely amorphous. XRD patterns of TiO2 powders calcinated at 400ºC is shown in Figure 3.1. 637 International Journal of Emerging Technology and Advanced Engineering Website: www.ijetae.com (ISSN 2250-2459, ISO 9001:2008 Certified Journal, Volume 3, Issue 1, January 2013) Fig 3.3 FT-IR spectrum of the synthesized nano TiO2 IV. CONCLUSION Fig.3.2 (a) SEM Morphology of calcinated titania powder at 400 0c Crystalline titania has been prepared by sol gel precipitation route using titanium tetra isopropoxide and subsequently annealed at 400°C. By controlling the conditions properly, nano-TiO2 powders of anatase form with the grain size of ~ 6 nm could be obtained. Surface morphological studies obtain from SEM micrograph showed that the particles with the spherical shapes are anatase in nature. In the FT-IR spectra, all the peaks observed were around 460-560 cm-1 due to stretching and bending vibrations of -OH groups. Acknowledgment We are thankful to principal, professors and lecturers, technical and non-technical staff those who are supported for the proposed research in the Department of Physics and Mechanical Engineering. Fig.3.2 (b) EDAX images of TiO2 FT-IR Spectroscopy Figure 3.3 represents the FT-IR spectra of sol-gel derived TiO2. The peaks at 3400 and 1650 cm−1 in the spectra are due to the stretching and bending vibration of the -OH group. In the spectrum of pure TiO2, the peaks at 550 cm-1 show stretching vibration of Ti-O and peaks at 1450 cm-1 shows stretching vibrations of Ti-O-Ti. Further EDAX confirms presence the Ti-O-Ti as shown in the figure 3.2 (b) K.Balachandran et al. [11]. REFERENCES [1 ] N. Castillo, D. Olguin, A. Conde- Gallardo, S. Jiménez- Sandoval, 2004 Structural and morphological properties of TiO2 thin films prepared by spray pyrolysis, Revista Mexicana De Física 50 (4) 382. [2 ] Dirk Verhulst, Bruce J. Sabacky, Timothy M. Spitler, Jan Prochazka, A new process for the production of nanosized TiO2 and other ceramic oxides by spray hydrolysis, www.altairnano.com/document/A2003-02-25verhulst.pdf [3 ] Pham Van Nho, Hoang Ngoc Thanh, I. Davoli, 2004 Characterization of nanocrystalline TiO2 films prepared by means of solution spray method, Proceedings of the 9th APPC, Hanoi 348 [4 ] S. Mahshid, M. Askari, M. S. Ghamsari,, N. Afshar, S. Lahuti. 2009 Mixed-phase TiO2 nanoparticles preparation using sol–gel method. Journal of Alloys and Compounds 47, 586–589 638 International Journal of Emerging Technology and Advanced Engineering Website: www.ijetae.com (ISSN 2250-2459, ISO 9001:2008 Certified Journal, Volume 3, Issue 1, January 2013) [5 ] C.C Wang and J.Y. Ying. 1999 Sol-Gel Synthesis and Hydrothermal Processing ofAnatase and Rutile Titania Nanocrystals. Chem. Mater. 11, 3113-3120 [6 ] H. Liu, W. Yang, Y. Ma, Y. Cao, J. Yao, J. Zhang and T. Hu.2003 Synthesis and Characterization of Titania Prepared by Using a Photoassisted Sol-Gel Method. Langmuir , 19, 3001-3005 [7 ] B. L. Bischof and M. A. Anderson. 1995 Peptization Process in the Sol-Gel Preparation of Porous Anatase (TiO2). Chem. Mater., 7, 1772-1778 [8 ] Jinghuan Zhang, Xin Xiao, Junmin Nan. 2010 Hydrothermalhydrolysis synthesis and photocatalytic properties of nano-TiO2 with an adjustable crystalline structure. Journal of Hazardous Materials 176,617–622 [9 ] Dongjin Byun, Yongki Jin, Bumjoon Kim, Joong Kee Lee, Dalkeun Park 2000 Photocatalytic TiO2 deposition by chemical vapor deposition. Journal of Hazardous Materials, 73,199-206 [10 ] B. D. Cullity, 1978 Elements of X-Ray Diffraction, Adison-Wesley. [11 ] K. Balachandran, R.Venckatesh, Rajeshwari Sivaraj, 2010 Synthesis of NanoTiO2-SiO2 composite using sol-gel method : Effect of size, surface morphology and thermal stability, IJEST, 2 (8), pp.36953700 [12 ] P. Chenga, C. Denga, M. Gub and A. X. Dai, 2008 “Effect of Urea on the Photoactivity of Titania Powder Prepared by Sol-Gel Method,” Materials Chemistry and Physics, Vol. 107, No. 1, January, pp. 77-81. [13 ] Z. Wang, U. Helmersson and P. Kall, 2002 “Optical Properties of Anatase TiO2 Thin Films Prepared by Aqueous Sol- Gel Process at Low Temperature.” Thin Solid Films, Vol. 405, No. 1-2, February, pp. 50-54. [14 ] N. Babaei et al, 2006 Preparation of TiO2/Al Nanocomposite Powders via the Ball milling, First International Congress on Nanoscience and Nanotechnology, Tehran (Iran), 18-20 December. Author’s Short Biography Kavitha T is a research Scholar in Nehru Memorial College. She obtained her M.Sc (Physics) from Nehru Memorial College and she has published papers in various prestigious journals. She has presented several papers in the proceedings of the national and international conferences in the field of Nanomaterials, Thin Films and solar cell. Rajendran A is working as a professor in Nehru memorial college Tiruchirapalli, Tamil Nadu, India. He obtained his M.Sc (Instrumentation) from Nehru Memorial College and Ph.D. from Poondi Pushpam Arts & Science College, Thanjavur, India. He published research papers in various national / international Journal / conferences in the field of Microprocessor, Microcontrollers and Nanomaterials. Durairajan A is a Mechanical Engineering student from KSR College of Engineering, Tiruchengode, Namakkal (DT), Tamil Nadu, India. He is a student Member of Professional Bodies like International Nano Science Community, Indian Society of Technical Education (ISTE), Indian Society For NonDestructive Testing (ISNT) and Indian Society of Mechanical Engineers (ISME). He was awarded “Young Investigator Award” in International conference on Mechanical & Industrial Engineering at Goa and he has published more than 20 papers in the proceedings of the National conferences and several papers in the proceedings of the International conferences and Prestigious Journals in the field of Nanomaterials, Automobile pollution control, and IC Engines. 639