Characterization of Sol-gel Prepared Silica Supported NiO-CuO Composites

2020 ◽  
Vol 42 (2) ◽  
pp. 164-164
Author(s):  
Samreen Zahra Samreen Zahra ◽  
Dr Narjis Naz Dr Narjis Naz ◽  
Dr Muhammad Zia ur Rehman Dr Muhammad Zia ur Rehman ◽  
Muhammad Irfan Asma Sheikh and Sania Izhar Muhammad Irfan Asma Sheikh and Sania Izhar
Keyword(s):  
Sol Gel ◽  
Copper Nitrate ◽  
Silica Matrix ◽  
Nitrate Hexahydrate ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Molar Ratios ◽  
Composite Formation ◽  
Sol Gel Process ◽  
Nickel Nitrate Hexahydrate

Silica (SiO2) supported nickel oxide-copper oxide (NiO-CuO) composites were synthesized through alkoxide route of sol-gel process using tetraethyl ortthosilicate (TEOS), nickel nitrate hexahydrate and copper nitrate trihydrate as precursors. A series of different compositions were prepared varying NiO:CuO molar ratios keeping all other process parameters constant. The gels thus obtained were calcined at a moderate temperature i.e. 500and#186;C for one hour. The crystal structure and thermal stability of metal oxide particles embedded in silica matrix were studied using X-ray diffraction technique (XRD) and differential scanning calorimetry (DSC-TGA) respectively. The purity of the composites was checked by Infrared spectroscopy (IR) whereas the composite formation was confirmed by scanning electron microscopy. The results revealed that crystals of NiO and CuO nanoparticles aggregated to form spheres of variable sizes were successfully embedded in the amorphous silica matrix composed of silica particles agglomerated to form clusters.

scholarly journals Preparation of (Pb,Ba)TiO3 powders and highly oriented thin films by a sol-gel process

2004 ◽  
Vol 19 (5) ◽  
pp. 1492-1498 ◽  
Author(s):  
Stacey W. Boland ◽  
Suresh C. Pillai ◽  
Wein-Duo Yang ◽  
Sossina M. Haile
Keyword(s):  
Thin Films ◽  
Sol Gel ◽  
Chelating Agent ◽  
Titanium Isopropoxide ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Force Microscopy ◽  
Molar Ratios ◽  
Atomic Force ◽  
Sol Gel Process

Solid solution Pb1-xBaxTiO3, with particular emphasis on Pb0.5Ba0.5TiO3, was prepared using a sol-gel process incorporating lead acetate trihydrate, barium acetate, and titanium isopropoxide as precursors, acetylacetone (2,4 pentanedione) as a chelating agent, and ethylene glycol as a solvent. The synthesis procedure was optimized by systematically varying acetylacetone: Ti and H2O:Ti molar ratios and calcination temperature. The resulting effects on sol and powder properties were studied using thermogravimetric analysis/differential scanning calorimetry, Fourier transform infrared spectroscopy, Brunauer-Emmett-Teller analysis, and x-ray diffraction (XRD). Crystallization of the perovskite structure occurred at a temperature as low as 450 °C. Thin films were prepared by spin coating on (100) MgO. Pyrolysis temperature and heating rate were varied, and the resultant film properties investigated using field-emission scanning electron microscopy, atomic force microscopy, and XRD. Under optimized conditions, highly oriented films were obtained at a crystallization temperature of 600 °C.

scholarly journals Effect of Various Solvent on the Synthesis of NiO Nanopowders by Simple Sol-Gel Methods and Its Characterization

2015 ◽  
Vol 15 (1) ◽  
pp. 50-55
Author(s):  
Sherly Kasuma Warda Ningsih
Keyword(s):  
Sol Gel ◽  
Spherical Shape ◽  
Nitrate Hexahydrate ◽  
Monoclinic Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sol Gel Process ◽  
Sem Micrograph ◽  
Nickel Nitrate Hexahydrate ◽  
Xrd Patterns

Synthesis of nickel oxide (NiO) with various solvents by simple sol-gel process has been done. NiO nanopowders were obtained by using nickel nitrate hexahydrate and sodium hydroxide 5 M were used as precursor and agent precipitator, respectively. The addition of various solvents that used in this research were aquadest, methanol and isopropanol. The powders were formed by drying in the temperature of 100-110 °C for 1 h and after heating at ±450 °C for 1 h. The products were obtained black powders. The products were characterized by Energy Dispersive X-Ray Fluorescence (ED-XRF), X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The ED-XRF pattern show that composition of NiO produced was 96.9%. The XRD patterns showed NiO forms were in monoclinic structure with aquadest solvent and cubic structure with methanol and isopropanol used. Crystal sizes of NiO particles produced with aquadest, methanol, isopropanol were obtained in the range 37.05; 72.16; 66.04 nm respectively. SEM micrograph clearly showed that powder had a spherical shape with uniform distribution size is 0.1-1.0 µm approximately.

Iron and Iron-oxide on Silica Nanocomposites Prepared by the Sol-gel Method

2002 ◽  
Vol 17 (3) ◽  
pp. 590-596 ◽  
Author(s):  
G. Ennas ◽  
M. F. Casula ◽  
G. Piccaluga ◽  
S. Solinas ◽  
M. P. Morales ◽  
...  
Keyword(s):  
Sol Gel ◽  
Silica Matrix ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Gel Method ◽  
Sol Gel Method ◽  
Silica Nanocomposites ◽  
Transmission Electron ◽  
Nanometric Particles

γ–Fe2O3/SiO2 and Fe/SiO2 nanocomposites, with a Fe/Si molar ratio of 0.25, were prepared by the sol-gel method starting from ethanolic solutions of tetraethoxysilane and iron (III) nitrate. After gelation the xerogels were oxidated or reduced. Samples were investigated by transmission electron microscopy, x-ray diffraction, differential scanning calorimetry, and thermogravimetry. Magnetic properties of the samples were investigated at room temperature (RT) and at 77 K. Nanometric particles supported in the silica matrix were obtained in all cases. Bigger particles (10 nm) were obtained in the case of Fe/SiO2 nanocomposites with respect to the γ–Fe2O3/SiO2 samples (5–8 nm). A slight effect of sol dilution on particle size was observed only in the case of γ–Fe2O3/SiO2 nanocomposites. A superparamagnetic behavior was shown at RT only by γ–Fe2O3/SiO2 nanocomposites. Iron-based composites exhibited coercivity values higher than 700 Oe at RT.

Synthesis of V2O5 Powders by EDTA Assistance Ultrasound Sol-Gel Process

2012 ◽  
Vol 512-515 ◽  
pp. 207-210
Author(s):  
Quan Wen ◽  
Jian Feng Huang ◽  
Li Yun Cao ◽  
Jian Peng Wu
Keyword(s):  
Activation Energy ◽  
Raw Materials ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Calcination Temperatures ◽  
Sol Gel Process ◽  
Ft Ir ◽  
Precursor Powders ◽  
Influence Of Ph

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.

A Calcination Technology for Ultrafine La3NbO7 Powder Prepared by Sol-Gel Process

2011 ◽  
Vol 412 ◽  
pp. 271-274
Author(s):  
Ying Li ◽  
Qiang Xu ◽  
Ling Dai
Keyword(s):  
Single Phase ◽  
Sol Gel ◽  
Average Particle Size ◽  
Complex Method ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Acid Complex ◽  
Calcination Process ◽  
Sol Gel Process

In order to prepare ultrafine La3NbO7 powder, a potential material for thermal barrier coatings, the calcination process of La3NbO7 was studied in this paper.The precursor of La3NbO7 was synthesized by using a citric acid complex method. A calcination process had been systematically investigated. The reaction temperature was determined by differential scanning calorimetry (DSC). The phase composition of powders was characterized by X-ray diffraction (XRD), and the morphology was obtained by scanning electron microscope (SEM). The results revealed that the single-phase La3NbO7 powder could be successfully prepared while the calcination temperature exceeded 800°C and a better morphology could be maintained at 800°C for 4 hours. Considering all above, an optimum calcination scheme was adopted at 800°C for 4 hours. The as-prepared La3NbO7 powders had a grain size of about 50nm and an average particle size of about 300nm.

Microstructural characteristics and photoluminescence performance of nanograined thermally treated CeO2-TiO2 xerogels

2007 ◽  
Vol 22 (5) ◽  
pp. 1182-1187
Author(s):  
Amita Verma ◽  
A.K. Srivastava ◽  
N. Karar ◽  
Harish Chander ◽  
S.A. Agnihotry
Keyword(s):  
Electron Microscopy ◽  
Crystallite Size ◽  
Sol Gel ◽  
Structural Features ◽  
X Ray Diffraction ◽  
Molar Ratios ◽  
Transmission Electron ◽  
Sol Gel Process ◽  
Crystallite Sizes ◽  
Thermally Treated

Nanostructured thermally treated xerogels have been synthesized using a sol-gel process involving cerium (Ce) chloride heptahydrate and titanium (Ti) propoxide mixed in different Ce:Ti molar ratios. Structural features of the xerogels have been correlated with their photoluminescence (PL) response. The crystallite sizes in the samples lie in the nanorange. The x-ray diffraction and transmission electron microscopy results have confirmed the coexistence of CeO2 and TiO2 nanocrystallites in these xerogels. In general, a decrease in the CeO2 crystallite size and an increase in the TiO2 crystallite size are observed in the xerogels as a function of Ti content. Scanning electron microscopy results have evidenced the evolution of ordered structure in the xerogels as a function of TiO2 content. Although both of the phases (CeO2 and TiO2) have exhibited PL in ultraviolet and visible regions, the major luminescence contribution has been made by the CeO2 phase. The largest sized CeO2 crystallites in 1:1 thermally treated xerogel have led to its highest PL response. PL emission in the xerogels is assigned to their nanocrystalline nature and oxygen vacancy-related defects.

Study of Pseudoboehmite Synthesis by Sol-Gel Process

2006 ◽  
Vol 45 ◽  
pp. 260-265 ◽  
Author(s):  
Antônio Hortêncio Munhoz Jr. ◽  
Leila Figueiredo de Miranda ◽  
G.N. Uehara
Keyword(s):  
Sol Gel ◽  
Thermo Gravimetric Analysis ◽  
Ammonium Hydroxide ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Sol Gel Process ◽  
Different Temperatures ◽  
Sol Gel Synthesis

A pseudoboehmite was obtained by sol-gel synthesis using aluminum nitrate as precursor. It was used a 2n full factorial design for studying the effect of the temperature of synthesis, the concentration of ammonium hydroxide, and the radiation dose in the product of sol-gel synthesis. The product of the synthesis was analyzed by scanning electron microscopy, x-ray diffraction of the product (after firing the pseudoboehmite at different temperatures), and it was also analyzed the temperature of endothermic and exothermic transformations using the thermo gravimetric analysis (TG) and differential scanning calorimetry (DSC). The X-ray diffraction data show that α-alumina was obtained at 1100o C.

ELABORATION AND CHARACTERIZATION OF La4Ni3O10 CATHODE MATERIAL (SOFC) BY SOL-GEL PROCESS

2011 ◽  
Vol 1326 ◽  
Author(s):  
Rene Fabian Cienfuegos ◽  
Leonardo Chávez Guerrero ◽  
Sugeheidy Carranza ◽  
Laurie Jouanin ◽  
Guillaume Marie ◽  
...  
Keyword(s):  
Cathode Material ◽  
Sol Gel ◽  
Synthesis Method ◽  
Solid Material ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Metallic Salts ◽  
Sol Gel Process

ABSTRACTThe goal in this study was to synthesize a lanthanum - nickel phase (Ruddlesden-Popper phases) La4Ni3O10. This material was prepared using a polymeric route. An easy synthesis method is presented in order to obtain an economical cathode material, which can be used in Solid Oxide Fuel Cells (SOFC). The polymeric precursors were prepared following the Castillo method. The originality of this work was to optimize the ratio HMTA/ metallic salts from 1 to 6. The obtained powders were characterized by thermal analysis; Differential Scanning Calorimetry (DSC Q10 Instrument TA), Thermogravimetric Analysis (TGA - Q50 Instrument TA-) and X-ray diffractometer (Bruker, D8 Advance diffractometer), in order to determine the crystallized phase. Experiments 5 and 6 did not present coagulation but after few days, solution 5 was transformed into a gel. Gels 2 to 5 were heated in order to obtain a solid material. These powders are characterized by thermogravimetric and thermo-differential methods. The powders obtained at 800, 900 and 1000°C were analyzed by X-ray diffraction and it was found that the temperature to get to the La4Ni3O10 phase was 1000ºC.

Crystallinity of Barium Titanate Nanoparticles Synthesized by Sol-Gel Method

2007 ◽  
Vol 350 ◽  
pp. 31-34 ◽  
Author(s):  
Teruhisa Makino ◽  
Masashi Arimura ◽  
Kunitaka Fujiyoshi ◽  
Yoko Yamashita ◽  
Makoto Kuwabara
Keyword(s):  
Barium Titanate ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
High Concentration ◽  
Scanning Calorimetry ◽  
Synthesis Conditions ◽  
Sol Gel Process ◽  
Aging Conditions ◽  
Barium Titanate Nanoparticles ◽  
Batio3 Nanoparticles

We synthesized barium titanate (BaTiO3) nanoparticles by sol-gel process and investigated their crystallization behavior using differential scanning calorimetry and X-ray diffraction. BaTiO3 nanoparticles with various degrees of crystallinity were obtained by adjusting synthesis conditions. Under aging conditions that do not allow dealcholization reaction to complete, many hydroxyl ligands remain in as-synthesized BaTiO3 nanoparticles, resulting in the formation of voids or defects in the nanoparticles after calcination. It is essential to use high concentration alkoxides precursor solutions for producing BaTiO3 nanoparticles with high crystallinity at low temperature.

scholarly journals Synthesis of ZnO-CuO Nanocomposite Aerogels by the Sol-Gel Route

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Rula M. Allaf ◽  
Louisa J. Hope-Weeks
Keyword(s):  
Electron Microscopy ◽  
Sol Gel ◽  
Average Crystallite Size ◽  
Copper Nitrate ◽  
Zinc Hydroxide ◽  
X Ray Diffraction ◽  
Molar Ratios ◽  
Transmission Electron ◽  
Composite Aerogels ◽  
Copper Composite

The epoxide addition sol-gel method has been utilized to synthesize porous zinc-copper composite aerogels in the zinc-to-copper molar ratios of 50 : 50 to 90 : 10. A two-step mixing approach has been employed to produce aerogels composed of nano- to micrometer sized particles. The aerogels were characterized by ultrahigh resolution scanning electron microscopy, transmission electron microscopy, and powder X-ray diffraction. The as-synthesized aerogels had a thin flake- or petal-like microstructure comprised of clustered flakes on two size scales; they were identified as being crystalline with the crystalline species identified as copper nitrate hydroxide, zinc hydroxide chloride hydrate, and zinc hydroxide nitrate hydrate. Annealing of the aerogel materials at a relatively low temperature (400°C) resulted in a complete phase transition of the material to give highly crystalline ZnO-CuO aerogels; the aerogels consisted of networked nanoparticles in the ~25–550 nm size range with an average crystallite size of ~3 nm and average crystallinity of 98%. ZnO-CuO aerogels are of particular interest due to their particular catalytic and sensing properties. This work emphasizes the versatility of this sol-gel route in synthesizing aerogels; this method offers a possible route for the fabrication of aerogels of different metal oxides and their composites.

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