Kinetics Transformation of Anatase to Rutile Phase for Titanium Dioxide Nanoparticles Prepared by Sol-Gel Method

2013 ◽  
Vol 756 ◽  
pp. 11-15
Author(s):  
Muneer M. Ba-Abbad ◽  
Abdul Amir Hassan Kadhum ◽  
Abu Bakar Mohamad ◽  
Mohd Sobri Takriff ◽  
Kamaruzzaman Sopian ◽  
...  

Simple sol-gel route was used to synthesis the TiO2 nanoparticles and examined by X-ray diffraction (XRD). The small particle size and uniform morphology of the TiO2 were found at different calcination temperatures. The kinetic study of phase changes from the anatase to rutile using the X-ray diffraction data with Avrami equation was investigated. The transformation of anatase to rutile was started after 500 °C and above by decreasing of XRD peaks intensity of anatase with rutile increased. The activation energy of the rutile phase was found lower which indicated that uniform shape and morphology of TiO2 nanoparticles. At same time, changes of activation energy value depended on the experimental conditions was observed.

2017 ◽  
Vol 17 (1) ◽  
pp. 26
Author(s):  
Atik Setyani ◽  
Emas Agus Prastyo Wibowo

PENGARUH PELARUT TERHADAP KARAKTERISTIK NANOPARTIKEL TITANIUM DIOKSIDA (TiO2) ABSTRAK Tujuan penelitian ini adalah untuk membandingkan jenis pelarut dalam proses pembentukan nanopartikel titanium dioksida dengan metode sol gel. Hasil karakterisasi dengan X-Ray Diffraction (XRD) menunjukkan bahwa penggunaan pelarut berpengaruh terhadap kristalinitas dan fasa material yang terbentuk. Berdasarkan Joint Committee on Powder Diffraction Standards (JCPDS) card nomor 84-1286 menunjukkan difraktogram nano TiO2 hasil sintesis sebagian besar merupakan fasa anatas. Hal ini terlihat dari nilai 2 teta yang diperoleh yaitu 24,45˚; 47,29˚; 53,18˚; 61,64˚ untuk fasa anatas dan 54,65˚; 74,16˚ untuk fasa rutil. Hanya saja persentase fasa anatas pada nano TiO2 menggunakan pelarut metanol lebih besar jika dibandingkan dengan hasil nano TiO2 dengan pelarut etanol. Berdasarkan perhitungan ukuran partikel nano TiO2 menggunakan persamaan Debye- Scherer didapatkan ukuran nano TiO2 menggunakan metanol sebesar 13.78 nm sedangkan  nano TiO2 menggunakan etanol sebesar 34.26 nm. Kata Kunci: Pelarut, sol-gel, titanium dioksida   EFFECT OF SOLVENTS ON THE CHARACTERITICS OF NANOPARTICLES TITANIUM DIOXIDE (TiO2) ABSTRACTThe purpose of this study was to compare the type of solvent in the process of formation of titanium dioxide nanoparticles with sol gel method. X-Ray Diffraction (XRD) characterization results indicate that the use of solvent effect on crystallinity and phase material formed. Based Joint Committee on Powder Diffraction Standards (JCPDS) 84-1286 card numbers show diffractogram nano TiO2 synthesized largely a anatas phase. This can be seen from a value of 2 theta obtained by the 24,45˚; 47,29˚; 53,18˚; 61,64˚ to phase anatas and 54,65˚; 74,16˚ for rutile phase. Only a small percentage of the nano TiO2 anatase phase using methanol solvent is greater when compared with the results of nano TiO2 with ethanol. Based on the calculation of nano TiO2 particle size using equation Debye- Scherer obtained nanosized TiO2 using methanol amounted to 13.78 nm while the nano TiO2 using ethanol amounted to 34.26 nm. Keywords: Solvent, sol-gel, titanium dioxide


PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0244511
Author(s):  
Fernando Gordillo-Delgado ◽  
Jakeline Zuluaga-Acosta ◽  
Gonzalo Restrepo-Guerrero

In this work, the effect of the inoculation of silver-incorporated titanium dioxide nanoparticles (Ag-TiO2 NPs) in spinach seeds was evaluated on certain growth, physiology and phytotoxicity parameters of the plants. This is an important crop for human consumption with high nutritional value due to their low calorie and fat content, providing various vitamins and minerals, especially iron. These NPs were obtained by means of the sol-gel method and heat treatment; the resulting powder material was characterized using X-ray diffraction and scanning electron microscopy and the influence of these NPs on plants was measured by estimating the germination rate, monitoring morphological parameters and evaluating phytotoxicity. The photosynthetic activity of the spinach plants was estimated through the quantification of the Ratio of Oxygen Evolution (ROE) by the photoacoustic technique. Samples of TiO2 powder with particle size between 9 and 43 nm were used to quantify the germination rate, which served to determine a narrower size range between 7 and 26 nm in the experiments with Ag-TiO2 NPs; the presence of Ag in TiO2 powder samples was confirmed by energy-dispersive X-ray spectroscopy. The analysis of variance showed that the dependent variable (plant growth) could be affected by the evaluated factors (concentration and size) with significant differences. The statistical trend indicated that the application of the Ag-TiO2 NPs suspension of lowest concentration and smallest particle size could be a promoting agent of the growth and development of these plants. The inoculation with NPs of 8.3 nm size and lowest concentration was related to the highest average ROE value, 24.6 ± 0.2%, while the control group was 20.2 ± 0.2%. The positive effect of the Ag-TiO2 NPs treatment could be associated to the generation of reactive oxygen species, antimicrobial activity, increased biochemical attributes, enzymatic activity or improvements in water absorption.


2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Aidong Tang ◽  
Yuehua Deng ◽  
Jiao Jin ◽  
Huaming Yang

A novel nanocomposite ZnFe2O4-TiO2/MCM-41 (ZTM) was synthesized by a sol-gel method and characterized through X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), N2adsorption-desorption, Raman spectroscopy, and ultraviolet visible (UV-vis) spectrophotometry. The results confirmed the incorporation of ZnFe2O4-TiO2nanoparticles inside the pores of the mesoporous MCM-41 host without destroying its integrity. ZnFe2O4nanoparticles can inhibit the transformation of anatase into rutile phase of TiO2. Incorporation of ZnFe2O4-TiO2within MCM-41 avoided the agglomeration of nanoparticles and reduced the band gap energy of TiO2to enhance its visible light photocatalytic activity. UV-vis absorption edges of ZTM nanocomposites redshifted with the increase of Zn/Ti molar ratio. The nanocomposite approach could be a potential choice for enhancing the photoactivity of TiO2, indicating an interesting application in the photodegradation and photoelectric fields.


2012 ◽  
Vol 66 (3) ◽  
Author(s):  
Khaled Haouemi ◽  
Fathi Touati ◽  
Néji Gharbi

AbstractTiO2 nanoparticles with different shapes and sizes were synthesised by the sol-gel route in Water/Brij78/Hexane reverse microemulsions. The aqueous cores of these microemulsions were used as nanoreactors to control sol-gel reactions. We studied the effect of water/surfactant mole ratio (W 0) on the morphology, and textural properties of the final products. The materials thus obtained were characterised by different techniques. Thermogravimetric and differential thermal analysis (TG-DTA) was used to study the thermal behaviour of the products and X-ray diffraction (XRD) to identify the crystalline phases. The morphological and textural properties of the products were determined by scattering electron microscopy (SEM) and the Brunauer-Emmett-Teller (BET) method, respectively. We also studied the influence of thermal treatment on the structure and size of the TiO2 particles. The effect of W 0 on the anatase-rutile phase transition temperature was investigated.


2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Ekaterina V. Borisova ◽  
Alexey V. Ignatov ◽  
Eugeni I. Get'man ◽  
Stanislav N. Loboda ◽  
Lyudmyla I. Ardanova ◽  
...  

Sodium europium silicate, NaEu9(SiO4)6O2, with apatite structure has been obtained and studied using X-ray diffraction and SEM. It has been shown that sodium sublimation does not take place upon synthesis by the sol-gel method. Rietveld refinement has revealed that sodium atoms are ordered and occupy the 4f position. O(4) atoms not related to silicate ions are placed at the centers of Eu(2) triangles. DC and AC electric conductivity and activation energy have been determined for the compound studied.


2012 ◽  
Vol 535-537 ◽  
pp. 2240-2244
Author(s):  
Wei Wei ◽  
Chang Shun Yu ◽  
Shao Jun Wang ◽  
Qing Da An

Nanosized TiO2 particles were synthesized by sol-gel method using ionic liquid as assistant. The samples were characterized by UV-vis diffuse reflectance spectra, X-ray diffraction (XRD), transmission electron microscopy (TEM). It was shown that the phase detectable was mainly rutile phase with uniform sphericity and the average size was 10nm. Along with the rise of sintering temperature, grain diameter became bigger. The photocatalytic activities of nanosized TiO2 were evaluated by the reduction yield in the presence of CO2 and water. The result showed that TiO2 catalysts has efficient photocatalytic activities, of which made with [OMIM]BF4 displayed the highest photocatalytic active in the experiment.


2010 ◽  
Vol 2010 ◽  
pp. 1-5 ◽  
Author(s):  
H. Mehranpour ◽  
M. Askari ◽  
M. Sasani Ghamsari ◽  
H. Farzalibeik

Titanium dioxide nanopowders were synthesized by the diffusion controlled sol-gel process (LaMer model) and characterized by DTA-TG, XRD, and SEM. The preparedTiO2nanoparticles have uniform size and morphology, and the phase transformation kinetics of obtained material was studied by interpretation of the X-ray diffraction patterns peaks on the base of Avrami equation. The stating point of anatase-rutile phase transformation temperature in the prepared nanoparticles was found between 100 and200°C. A decreasing trend on the intensity of X-ray peaks of anatase phase was observed up to600°Cwhen the presence of the rutile phase became predominant. Results indicated that the transition kinetics of the diffusion controlled prepared nanoparticles was begun at low temperature, and it can be concluded that the nucleation and growth sites in these particles were more than other. However, it has been found that the nucleation activation energy of rutile phase was 20 kj/mol, and it is the lowest reported activation energy.


2012 ◽  
Vol 512-515 ◽  
pp. 207-210
Author(s):  
Quan Wen ◽  
Jian Feng Huang ◽  
Li Yun Cao ◽  
Jian Peng Wu

V2O5 powders were successfully synthesized by the EDTA assistanced ultrasound sol-gel process using NH4VO3 and EDTA, NH3•H2O as raw materials. The synthesized activation energy and the influence of pH values and the calcination temperatures on the phases and microstructures of powders were particularly investigated. The precursor powders and the V2O5 powders were characterized by X-ray diffraction (XRD), fourier transform inelectron microscopy (FT-IR), scanning electron microscopy (SEM) and differential scanning calorimetry-thermal gravimetric (DSC-TG). Results show that the obtained products exhibit good crystallization under the conditions of pH=4, calcination temperature 400~500 °C and calcination time 0.5 h during the synthesizing process. The as-prepared V2O5 powders show preferred growth orientation along (001) plane at the pH=4. By DSC analysis, the ultrasonic cavitation result in the decrease in synthesized activation energy obviously than that was prepared without ultrasonic irradiation.


2011 ◽  
Vol 76 (11) ◽  
pp. 1335-1346 ◽  
Author(s):  
Jing Wei ◽  
Xin Tan ◽  
Tao Yu ◽  
Lin Zhao

A series of copper-modified titanium dioxide (Cu/TiO2) nanoparticles were synthesized via one-step sol-gel method. The crystal structure and chemical properties were characterized using X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The Cu/TiO2nanoparticles were applied to CO2photoconversion and the yield of formaldehyde was used to evaluate the photocatalytic performance. The optimum amount of copper modifying was 0.6 wt.% and the yield of formaldehyde was 946 μmol/gcatunder UV illumination for 6 h. 20 wt.% Cu/TiO2also performed a high photocatalytic activity, which yielded 433 μmol/gcatformaldehyde under UV illumination for 6 h.


1990 ◽  
Vol 180 ◽  
Author(s):  
Z. Fathi ◽  
I. Ahmad ◽  
D.E. Clark

ABSTRACTMicrowave energy has been used in a novel processing method. The relationship between processing, structure and properties of sol-gel-derived potassium niobate sol as well as thin films has been investigated. A comparison has been established between microwave and conventional heating for drying, calcining and crystallizing sol-gel-derived samples. Structural and phase changes were monitored by thermogravimetric analysis (TGA), differential thermal analysis (DTA) and x-ray diffraction (XRD).


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