scholarly journals Synthesis and Characterization of Polystyrene/CuO-Fe2O3 Nanocomposites from Natural Materials as Hydrophobic Photocatalytic Coatings

Crystals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 31
Author(s):  
Ratnawulan Ratnawulan ◽  
Ramli Ramli ◽  
Ahmad Fauzi ◽  
Sukma Hayati AE
Keyword(s):  
Contact Angle ◽  
Calcination Temperature ◽  
Sessile Drop ◽  
Sol Gel ◽  
Basic Material ◽  
Copper Ferrite ◽  
Natural Materials ◽  
Hydrophobic Coating ◽  
Calcination Temperatures

This study reports on the synthesis, characterization of polystyrene(PS)/CuO-Fe2O3 nanocomposites, and their application as hydrophobic coatings. CuO and Fe2O3 materials were synthesized from natural materials by the milling method. Meanwhile, the PS/CuO-Fe2O3 nanocomposites were synthesized by the sol-gel method. Furthermore, the hydrophobic coating on the glass substrate was made by the spin-coating. To obtain highest value of contact angle, the composition of both CuO and Fe2O3 in nanocomposite as well as calcination temperatures were varied. Sample characterization was conducted using X-ray diffraction (XRD), scanning electron microscopy (SEM), and ultraviolet visible (Uv-Vis) spectrophotometry analysis. The Sessile drop method was used to determine the contact angle of the layer. The results showed that PS/CuO-Fe2O3 nanocomposite was successfully obtained with a crystal size between 40–52 nm and grain size of 92 nm. In addition to the basic material of composites, hematite and tenorite, the presence of copper ferrite phase was also identified. The CuO-Fe2O3 composition and its large calcination temperature also plays an effective role in the magnitude of the contact angle. The highest value of contact angle obtained was 125.46° at 3:1 composition and calcination temperature of 200 °C. We found that the PS/CuO-Fe2O3 composite was hydrophobic, but the photocatalyst activity was very small at 0.24%.

scholarly journals SYNTHESIS AND CHARACTERIZATION OF Fe2O3 NANOPARTICLES USING Averrhoa bilimbi AS BIOMATERIAL CHELATING AGENT FOR NANOFLUIDS APPLICATION

2017 ◽  
Vol 13 (2) ◽  
pp. 133 ◽  
Author(s):  
Arie Hardian ◽  
Alvi Aristia Ramadhiany ◽  
Dani Gustaman Syarif ◽  
Senadi Budiman
Keyword(s):  
Calcination Temperature ◽  
Sol Gel ◽  
Chelating Agent ◽  
Xrd Analysis ◽  
Solid Particles ◽  
X Ray Diffraction ◽  
Calcination Temperatures ◽  
Basic Fluid ◽  
Sol Gel Synthesis

<p>The aim of this work was to determine the effect of calcination temperature on the characteristics of Fe<sub>2</sub>O<sub>3</sub> nanoparticles (NPs) in sol-gel synthesis. The obtained Fe<sub>2</sub>O<sub>3 </sub>NPs was then used as material for preparation of Fe<sub>2</sub>O<sub>3</sub>-water nanofluids. Nanofluids is a mixture between basic fluid like water and 1 - 100 nm solid particles (nanoparticles). Nanoparticles of Fe<sub>2</sub>O<sub>3</sub> have been synthesized from the local mineral Jarosite using sol-gel method by using starfruit (<em>Averrhoa bilimbi</em>) extracts as the chelating agent. The calcination temperature was then varied from 500 ºC to 700 ºC for 5 hours. Based on the X-Ray Diffraction (XRD) analysis, the diffraction pattern of obtained Fe<sub>2</sub>O<sub>3</sub> was relevant with the JCPDS data No. 33-0664 for α-Fe<sub>2</sub>O<sub>3 </sub>with hexagonal crystallite system. The crystallite size (Scherrer’s Equation) of obtained α-Fe<sub>2</sub>O<sub>3</sub> nanoparticles at calcination temperatures of 500 ºC, 600 ºC and 700 ºC was 50 nm, 48 nm and 40 nm, respectively. The Surface Area of Fe<sub>2</sub>O<sub>3</sub> NPs at temperature of 500 ºC, 600 ºC and 700 ºC was 45.45 m<sup>2</sup>/g; 26.91 m<sup>2</sup>/g and 17.51 m<sup>2</sup>/g, respectively. Fe<sub>2</sub>O<sub>3</sub>-water nanofluids was relativly stable with zeta potential of -39.60 mV; -46.37 mV and -41.57 mV, respectively for 500 ºC, 600 ºC and 700 ºC calcination temperature. The viscosity of Fe<sub>2</sub>O<sub>3</sub>-water nanofluids was higher than the viscosity of water. The critical heat flux (CHF) value of water-Fe<sub>2</sub>O<sub>3</sub> nanofluids was higher than the CHF water. The highest CHF value for nanofluids was obtained by using α-Fe<sub>2</sub>O<sub>3</sub> nanoparticles with calcination temperature of 600 ºC which 34.99 % of increment compare to the base fluid (water).</p>

The effect of silver concentration and calcination temperature on structural and optical properties of ZnO:Ag nanoparticles

2015 ◽  
Vol 29 (01) ◽  
pp. 1450254 ◽  
Author(s):  
M. Shayani Rad ◽  
A. Kompany ◽  
A. Khorsand Zak ◽  
M. E. Abrishami
Keyword(s):  
Calcination Temperature ◽  
Sol Gel ◽  
Visible Emission ◽  
X Ray Diffraction ◽  
Ag Nps ◽  
Zno Nps ◽  
Calcination Temperatures ◽  
Transmission Electron ◽  
Xrd Patterns ◽  
Average Size

Pure and silver added zinc oxide nanoparticles ( ZnO -NPs and ZnO : Ag -NPs) were synthesized through a modified sol–gel method. The prepared samples were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM) and photoluminescence (PL) spectroscopy. In the XRD patterns, silver diffracted peaks were also observed for the samples synthesized at different calcination temperatures of 500°C, 700°C, 900°C except 1100°C, in addition to ZnO . TEM images indicated that the average size of ZnO : Ag -NPs increases with the amount of Ag concentration. The PL spectra of the samples revealed that the increase of Ag concentration results in the increase of the visible emission intensity, whereas by increasing the calcination temperature the intensity of visible emission of the samples decreases.

scholarly journals Highly Selective Syngas/H2 Production via Partial Oxidation of CH4 Using (Ni, Co and Ni–Co)/ZrO2–Al2O3 Catalysts: Influence of Calcination Temperature

Processes ◽  
2019 ◽  
Vol 7 (3) ◽  
pp. 141 ◽  
Author(s):  
Anis Hamza Fakeeha ◽  
Yasir Arafat ◽  
Ahmed Aidid Ibrahim ◽  
Hamid Shaikh ◽  
Hanan Atia ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Calcination Temperature ◽  
Partial Oxidation ◽  
Sol Gel ◽  
Analytical Techniques ◽  
Oxygen Storage Capacity ◽  
H2 Production ◽  
Oxygen Storage ◽  
Calcination Temperatures ◽  
Metal Support Interaction

In this study, Ni, Co and Ni–Co catalysts supported on binary oxide ZrO2–Al2O3 were synthesized by sol-gel method and characterized by means of various analytical techniques such as XRD, BET, TPR, TPD, TGA, SEM, and TEM. This catalytic system was then tested for syngas respective H2 production via partial oxidation of methane at 700 °C and 800 °C. The influence of calcination temperatures was studied and their impact on catalytic activity and stability was evaluated. It was observed that increasing the calcination temperature from 550 °C to 800 °C and addition of ZrO2 to Al2O3 enhances Ni metal-support interaction. This increases the catalytic activity and sintering resistance. Furthermore, ZrO2 provides higher oxygen storage capacity and stronger Lewis basicity which contributed to coke suppression, eventually leading to a more stable catalyst. It was also observed that, contrary to bimetallic catalysts, monometallic catalysts exhibit higher activity with higher calcination temperature. At the same time, Co and Ni–Co-based catalysts exhibit higher activity than Ni-based catalysts which was not expected. The Co-based catalyst calcined at 800 °C demonstrated excellent stability over 24 h on stream. In general, all catalysts demonstrated high CH4 conversion and exceptionally high selectivity to H2 (~98%) at 700 °C.

Hydrophilic and Photocatalytic Performances of Y-Doped Titanium Dioxide Thin Films

2013 ◽  
Vol 651 ◽  
pp. 103-108
Author(s):  
Jun Du ◽  
Yan Bin Yu ◽  
Jing Jing Huang ◽  
Hua Qiang Fu ◽  
Bu Hui Li ◽  
...  
Keyword(s):  
Thin Films ◽  
Methylene Blue ◽  
Contact Angle ◽  
Photocatalytic Activity ◽  
Calcination Temperature ◽  
Crystalline Phase ◽  
Sol Gel ◽  
Tetrabutyl Titanate ◽  
Continuous Increase ◽  
Photocatalytic Performances

Pure and Y-doped TiO2 thin films are prepared on glass by sol-gel method. Tetrabutyl titanate was used as Ti precursors. The chemical composition, structure and properties of TiO2 thin films are characterized by XRD, FT-IR, UV-Vis and Optical Contact Angle Measuring Instrument. Their photocatalytic performances were studied in detail by the methylene blue degradation model. The results show that the crystalline phase of Y2Ti2O7 is formed and the phase transformation from anatase to rutile is restrained when Y is doped in the TiO2 thin films. However, with the continuous increase in calcination temperature, its photocatalytic activity decreases, because the anatase will transform to the rutile. The proper amount of Y doping will cause the lattice to expand, the new defects will form and the smaller band-gap energy will be revealed. Thus, the absorption ability toward the ultraviolet can be improved, the redshift of the absorption band can also be found. As the results of it, the hydrophilicity and photocatalytic efficiency can improved. Furthermore, the photocatalytic activity increases with the hydrophilicity. When the calcination temperature of thin films is 450oC and the Y-doping is 0.3%, the main crystalline phase of the samples is the anatase, the contact angle is only 13.7o and the degradation ratio of methylene blue reached 98.84%.

Synthesis and Characterization of Stabilized Tetragonal Nano Zirconia by Precipitation Method

2019 ◽  
Vol 56 ◽  
pp. 142-151
Author(s):  
Hassan Shokry ◽  
Marwa Elkady ◽  
Hesham Hamad
Keyword(s):  
Phase Transformation ◽  
Crystallite Size ◽  
Calcination Temperature ◽  
Average Crystallite Size ◽  
Precipitation Method ◽  
Synthesis And Characterization ◽  
Calcination Temperatures ◽  
Ft Ir ◽  
20 Nm

Nano sized ZrO2 nanopowder was synthesized by precipitation method. Phase transformation was investigated as a function of calcination temperature by XRD, SEM , and FT-IR. It is indicated that the thermal anneling from 400 to 800 °C resulted in increasing the average crystallite size from 12 to 20 nm. As the calcination temperature increased, the crystallite size and the agglomeration were increased. The increase in the monoclinic content and grain growth are caused by the calcination temperatures even calcination at 800 °C.

Effect of Processing Parameters of Hydrophobic Film on Ceramic Tile

2017 ◽  
Vol 263 ◽  
pp. 97-102
Author(s):  
Prapatsorn Prathungthai ◽  
Sutham Srilomsak ◽  
Wimonlak Sutapun ◽  
Sukasem Watcharamaisakul ◽  
Lada Punsukumtana
Keyword(s):  
Contact Angle ◽  
Research Study ◽  
Sessile Drop ◽  
Sol Gel ◽  
Processing Parameters ◽  
Measuring Apparatus ◽  
Optical Contact ◽  
Water Contact ◽  
Curing Conditions ◽  
Design Expert

In this research study the fabricated of hydrophobic of SiO2 nanoparticles was modified with tetraethylorthosilicate (TEOS), poly-(dimethylsiloxane) (PDMS) and methyltriethoxysilane (MTES) by using a sol-gel method. The effects of precursors, coating techniques and curing conditions were investigated. A water contact angle (WCA) measurement done using a sessile drop method with an optical contact measuring apparatus. Morphologies of the hydrophobic films were depicted using scanning electron microscopy (SEM). All data were analyzed using Design Expert® software. Results shown that a morphology of hydrophobic films had nanoroughness as evidenced by high contact angle. The largest predicted WCA of these is 150.306 degrees, which will be obtained with a TEOS:SiO2:PDMS:MTES ratio equal to 7.00:3.374:2.75:3.00 wt.% respectively. It is coated using a dipping technique and oven cured at 400°C.

Phase Evolution and Crystallite Size of Ni0.25Zn0.75Fe2O4 at Different Calcination Temperatures

2014 ◽  
Vol 925 ◽  
pp. 290-294 ◽  
Author(s):  
Beh Hoe Guan ◽  
Hasan Soleimani ◽  
Noorhana Yahya ◽  
Noor Rasyada Ahmad Latiff
Keyword(s):  
Crystallite Size ◽  
Calcination Temperature ◽  
Temperature Increase ◽  
Spinel Structure ◽  
Sol Gel ◽  
Phase Evolution ◽  
Calcination Temperatures ◽  
Crystallite Sizes ◽  
Gel Technique ◽  
Scherrer Equation

The effects of calcination temperature varying from 700 to 1100°C on the phase evolution and crystallite size of Ni0.25Zn0.75Fe2O4 synthesized using Sol-Gel technique have been investigated. XRD results showed that the Fe2O3 phase was formed in Ni0.25Zn0.75Fe2O4 in the lower calcination temperature. The crystallization increased as the calcination temperature increased and the crystallite sizes of the Ni0.25Zn0.75Fe2O4 calculated from Scherrer equation were found to be ranged from 16 to 62 nm which increased when calcination temperature increase. Raman results further confirmed the presence of spinel structure in the samples.

scholarly journals Tuning the Pore Structures of Organosilica Membranes for Enhanced Desalination Performance via the Control of Calcination Temperatures

Membranes ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 392
Author(s):  
Rong Xu ◽  
Qian Liu ◽  
Xiuxiu Ren ◽  
Peng Lin ◽  
Jing Zhong
Keyword(s):  
Calcination Temperature ◽  
Sol Gel ◽  
Great Promise ◽  
Oh Groups ◽  
High Salinity Water ◽  
Calcination Temperatures ◽  
Pore Structures ◽  
Salinity Water ◽  
Gel Technique ◽  
Acid Catalyzed

Microporous organosilica membranes based on 1,2-bis(triethoxylsilyl)ethane (BTESE) were fabricated via an acid-catalyzed sol-gel technique. In the preparation process, the calcination temperature plays a significant role in structural and surface properties of the organosilica networks. With an increase in calcination temperature, the surface hydrophilicity decreased due to the enhanced condensation of Si-OH groups in the networks. N2 adsorption results suggest that the pore structures of BTESE membranes was clearly dependent on the calcination temperature. The pore sizes of the membranes were quantitatively determined by using the Normalized Knudsen-based permeance (NKP) model. In pervaporation tests, the membranes with higher calcination temperatures showed higher salt rejections and lower water permeances, which was attributed to the changes in pore size and surface chemistry of pore walls. The BTESE membranes calcined at 200 °C exhibited superior hydrothermal stability in temperature cycles up to 70 °C and high reproducibility in concentration cycles with NaCl concentrations of 0.2–13 wt%, showing great promise for desalination applications of high-salinity water.

Preparation and Characterization of NiO Nanoparticles

2015 ◽  
Vol 31 ◽  
pp. 93-102 ◽  
Author(s):  
Farrakh Shahzad ◽  
Karl Ettinger ◽  
Ilse Letofsky-Papst ◽  
Julia Weber ◽  
Peter Knoll
Keyword(s):  
Crystallite Size ◽  
Calcination Temperature ◽  
Ph Value ◽  
Sol Gel ◽  
Systematic Change ◽  
X Rays ◽  
Nio Nanoparticles ◽  
Calcination Time ◽  
Transmission Electron

NiO nanoparticles are successfully prepared by sol-gel technique. A systematic change in preparation parameters like calcination temperature, calcination time and pH value has been done in order to study the influence on crystallite size. The prepared samples are characterized by X-ray diffractometer, Transmission electron microscopy, Energy dispersive x-rays analysis and Raman spectroscopy. It is shown that crystallite size mainly depends on the calcination temperature rather than pH value or calcination time.

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