Fabrication of clay soil/CuFe2O4 nanocomposite toward improving energy and shielding efficiency of buildings

AbstractIn this research, the energy and shielding efficiency of brick, fabricated by clay soil, as a practical building material was reinforced using CuFe2O4 nanoparticles. Initially, the nanoparticles were fabricated using the sol–gel method and then loaded in the brick matrix as a guest. The architected samples were characterized by X-ray powder diffraction (XRD), Fourier transform infrared (FTIR), diffuse reflection spectroscopy (DRS), field emission scanning electron microscopy (FE-SEM), High-resolution transmission electron microscopy (HRTEM), vibrating-sample magnetometer (VSM), differential scanning calorimetry (DSC) thermograms, and vector network analyzer (VNA) analyses. IR absorption of the tailored samples was monitored under an IR source using an IR thermometer. IR absorption and energy band gap attested that inserting the nanoparticles in brick medium led to the acceleration of a warming brick, desirable for energy efficiency in cold climates. It is worth noting that the brick/CuFe2O4 nanocomposite achieved a strong reflection loss (RL) of 58.54 dB and gained an efficient bandwidth as wide as 4.22 GHz (RL > 10 dB) with a thickness of 2.50 mm, meanwhile it shielded more than 58% of the electromagnetic waves at X-band by only a filler loading of 10 wt%. The microwave absorbing and shielding characteristics of the composite are mainly originated from conductive loss, electron hopping, natural and exchange resonance, relaxation loss, secondary fields, as well as eddy current loss. Interestingly, the shielding property of the nanocomposite was significantly generated from its absorbing features, reducing the secondary electromagnetic pollutions produced by the shielding materials applying the impedance mismatching mechanism.

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Process for Producing Nano-Alpha-Alumina Powder

ISRN Nanotechnology ◽

10.5402/2011/692594 ◽

2011 ◽

Vol 2011 ◽

pp. 1-5 ◽

Cited By ~ 6

Author(s):

Fatemeh Mirjalili ◽

Luqman Chuah Abdullah ◽

Hasmaliza Mohamad ◽

A. Fakhru'l-Razi ◽

A. B. Dayang Radiah ◽

...

Keyword(s):

Electron Microscopy ◽

Particle Size ◽

Sol Gel ◽

Alumina Nanoparticles ◽

Alumina Powder ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Transmission Electron ◽

Stirring Time ◽

Particle Size And Shape

This paper is trying to explore the effect of stirring time on the synthesis of nano-α-Alumina particles. In this study, alumina nanoparticles were synthesized through alkoxide route using sol-gel method, where aqueous solutions of aluminum isopropoxide and 0.5 M aluminum nitrate nanohydrate were used for preparing alumina sol. Sodium dodecylbenzen sulfonate (SDBS) was used as the surfactant stabilizing agent. The prepared solution was stirred at different times (24, 36, 48, and 60 hours) at 60°C. The Samples were, then, characterized by X-ray diffraction, thermogravimetry analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and Transmission Electron Microscopy(TEM) . The introduction of different stirring times affected the particle size and shape and the degree of aggregation. By increasing the stirring time, (starting from 24 to 48 hours) the particle size decreased, but agglomeration became hard for 60 hours of stirring time. The finest particle size (20–30 nm) was obtained at 48-hour stirring time.

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Sol-gel derived Nd1/3La1/3Ca1/3MnO3: Phase evolution and preparation of films and nanopowders

Journal of Materials Research ◽

10.1557/jmr.2007.0221 ◽

2007 ◽

Vol 22 (6) ◽

pp. 1737-1743 ◽

Cited By ~ 1

Author(s):

A. Pohl ◽

G. Westin

Keyword(s):

Electron Microscopy ◽

Heat Treatment ◽

Single Phase ◽

Sol Gel ◽

Phase Evolution ◽

Perovskite Oxide ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Cell Parameters ◽

Transmission Electron

An all-alkoxide sol-gel route to the formation of Nd1/3La1/3Ca1/3MnO3thin films and powders has been developed. The microstructural evolution on heat treatment of the gel to yield the perovskite oxide was monitored by means of thermogravimetric analysis-differential scanning calorimetry, powder x-ray diffraction (XRD), Fourier transform infrared spectroscopy, and transmission electron microscopy (TEM)-energy dispersive spectroscopy (EDS). It was found that the amorphous gel consists of hydrated oxo-carbonate without organic residues, and on heating it decomposes in several steps, finally forming single-phase perovskite at 680 °C. Further heating results in only slight changes in the cell parameters and crystal growth. Films were prepared by spin coating, followed by heat treatment in air to a temperature of 800 °C, and studied by scanning electron microscopy, TEM-EDS, and XRD. Films on Al2O3were more porous, while films on Pt–TiO2–SiO2–Si were rather dense and consisted of areas with different crystal orientations.

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Synthesis and characteristics of nanocrystalline materials in Ti, B, C and N containing system

Open Physics ◽

10.2478/s11534-010-0121-x ◽

2011 ◽

Vol 9 (2) ◽

Cited By ~ 5

Author(s):

Anna Biedunkiewicz ◽

Paweł Figiel ◽

Urszula Gabriel ◽

Marta Sabara ◽

Stanisław Lenart

Keyword(s):

Electron Microscopy ◽

Sol Gel ◽

Ceramic Materials ◽

Nanocrystalline Powders ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Transmission Electron ◽

C And N ◽

Two Stages

AbstractIn this work, the results of investigations of manufacturing ceramic materials on the basis of Ti, B, C and N containing systems are presented. The nanocrystalline ceramics were synthesized using a non-hydrolytic sol-gel method. The process was carried out in two stages. In the first low-temperature stage the precursor was obtained. The synthesis of ceramic phases, however, was conducted in the second high-temperature stage, in an argon atmosphere. Depending on the initial composition of the mixtures, the temperature and the time, the following products were obtained: TiCx, TiCxN1−x, TiB2 and B4C.The course of the process was investigated by thermogravimetric and differential scanning calorimetry methods (TG-DSC) coupled with mass spectrometry (MS). The solid state products were identified with use of X-ray diffraction (XRD). The size of the crystallites was estimated by the Scherrer method. The structure and morphology images of nanocrystalline powders were obtained using scanning electron microscopy (SEM) and transmission electron microscopy (TEM).

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Photocatalysis Property of Titania-Based Thin Films with Covalent Grafting PANi as Sensitizer

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.549.470 ◽

2012 ◽

Vol 549 ◽

pp. 470-473 ◽

Cited By ~ 2

Author(s):

Hong Quan Liu ◽

Fang Lian ◽

Lin Zhang ◽

Meng Liu

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Sol Gel ◽

Composite Films ◽

Tetrabutyl Titanate ◽

Porous Films ◽

Scanning Calorimetry ◽

Transmission Electron ◽

Covalent Grafting ◽

Titania Sol

Polyaniline sensitized titania thin film were fabricated by spin-coating from Ti-precursor containing PEG as surfactant via a sol-gel technique, in which titania-sol was synthesized by hydrolysis of tetrabutyl titanate in water-alcohol solution. The films were characterized by X-ray diffraction, high resolution transmission electron microscopy, field-emission scanning electron microscopy, thermal gravity-differential scanning calorimetry, and tested under self-made photocatalysis instrument. The results showed the synthesized porous films provided the active surfaces for self-polymerization of aniline. Compared with bare TiO2 thin films, the composite films displayed a enhanced photocatalytic activity and could be the potential photocatalyst for indoor air decontamination or self-cleaning films.

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Blue Emitting BaAl2O4:Ce3+ Nanophosphors with High Color Purity and Brightness for White LEDs

Microscopy and Microanalysis ◽

10.1017/s1431927619014958 ◽

2019 ◽

Vol 25 (6) ◽

pp. 1466-1470 ◽

Cited By ~ 1

Author(s):

Rituparna Chatterjee ◽

Subhajit Saha ◽

Karamjyoti Panigrahi ◽

Uttam Kumar Ghorai ◽

Gopes Chandra Das ◽

...

Keyword(s):

Electron Microscopy ◽

Field Emission ◽

Sol Gel ◽

Blue Emission ◽

Diffraction Field ◽

White Leds ◽

Display Devices ◽

Transmission Electron ◽

Structure Morphology ◽

The Impact

AbstractIn this work, strongly blue emitting Ce3+-activated BaAl2O4 nanophosphors were successfully synthesized by a sol–gel technique. The crystal structure, morphology, and microstructure of the nanophosphors have been studied by X-ray powder diffraction, field emission scanning electron microscopy, and high-resolution transmission electron microscopy. The photoluminescence spectra show the impact of concentration variation of Ce3+ on the photoluminescence emission of the phosphor. These nanophosphors display intense blue emission peaking at 422 nm generated by the Ce3+ 5d → 4f transition under 350 nm excitation. Our results reveal that this nanophosphor has the capability to take part in the emergent domain of solid-state lighting and field-emission display devices.

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Effects of Recycled Fe2O3 Nanofiller on the Structural, Thermal, Mechanical, Dielectric, and Magnetic Properties of PTFE Matrix

Polymers ◽

10.3390/polym13142332 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2332

Author(s):

Ahmad Mamoun Khamis ◽

Zulkifly Abbas ◽

Raba’ah Syahidah Azis ◽

Ebenezer Ekow Mensah ◽

Ibrahim Abubakar Alhaji

Keyword(s):

Electron Microscopy ◽

High Energy ◽

Filler Loading ◽

Complex Permeability ◽

X Ray Diffraction ◽

Thermal Expansion Coefficients ◽

Transmission Electron ◽

Energy Ball ◽

Hematite Fe2o3 ◽

Ptfe Composites

The purpose of this study was to improve the dielectric, magnetic, and thermal properties of polytetrafluoroethylene (PTFE) composites using recycled Fe2O3 (rFe2O3) nanofiller. Hematite (Fe2O3) was recycled from mill scale waste and the particle size was reduced to 11.3 nm after 6 h of high-energy ball milling. Different compositions (5–25 wt %) of rFe2O3 nanoparticles were incorporated as a filler in the PTFE matrix through a hydraulic pressing and sintering method in order to fabricate rFe2O3–PTFE nanocomposites. The microstructure properties of rFe2O3 nanoparticles and the nanocomposites were characterized through X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and high-resolution transmission electron microscopy (HRTEM). The thermal expansion coefficients (CTEs) of the PTFE matrix and nanocomposites were determined using a dilatometer apparatus. The complex permittivity and permeability were measured using rectangular waveguide connected to vector network analyzer (VNA) in the frequency range 8.2–12.4 GHz. The CTE of PTFE matrix decreased from 65.28×10−6/°C to 39.84×10−6/°C when the filler loading increased to 25 wt %. The real (ε′) and imaginary (ε″) parts of permittivity increased with the rFe2O3 loading and reached maximum values of 3.1 and 0.23 at 8 GHz when the filler loading was increased from 5 to 25 wt %. A maximum complex permeability of 1.1−j0.07 was also achieved by 25 wt % nanocomposite at 10 GHz.

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Study on Structure, Thermal Behavior, and Viscoelastic Properties of Nanodiamond-Reinforced Poly (vinyl alcohol) Nanocomposites

Polymers ◽

10.3390/polym13091426 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1426

Author(s):

Tomáš Remiš ◽

Petr Bělský ◽

Tomáš Kovářík ◽

Jaroslav Kadlec ◽

Mina Ghafouri Azar ◽

...

Keyword(s):

Electron Microscopy ◽

Mechanical Analysis ◽

Single Step ◽

Poly Vinyl Alcohol ◽

Scanning Calorimetry ◽

X Ray Scattering ◽

Transmission Electron ◽

Primary Particles ◽

Solution Casting Method ◽

Average Size

In this work, advanced polymer nanocomposites comprising of polyvinyl alcohol (PVA) and nanodiamonds (NDs) were developed using a single-step solution-casting method. The properties of the prepared PVA/NDs nanocomposites were investigated using Raman spectroscopy, small- and wide-angle X-ray scattering (SAXS/WAXS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA). It was revealed that the tensile strength improved dramatically with increasing ND content in the PVA matrix, suggesting a strong interaction between the NDs and the PVA. SEM, TEM, and SAXS showed that NDs were present in the form of agglomerates with an average size of ~60 nm with primary particles of diameter ~5 nm. These results showed that NDs could act as a good nanofiller for PVA in terms of improving its stability and mechanical properties.

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Biocompatibility Characteristics of Titanium Coated with Multi Walled Carbon Nanotubes—Hydroxyapatite Nanocomposites

Materials ◽

10.3390/ma12020224 ◽

2019 ◽

Vol 12 (2) ◽

pp. 224 ◽

Cited By ~ 5

Author(s):

Jung-Eun Park ◽

Yong-Seok Jang ◽

Tae-Sung Bae ◽

Min-Ho Lee

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Sol Gel ◽

Pure Titanium ◽

Cell Proliferation And Differentiation ◽

Transmission Electron ◽

Proliferation And Differentiation ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

Multi walled carbon nanotubes-hydroxyapatite (MWCNTs-HA) with various contents of MWCNTs was synthesized using the sol-gel method. MWCNTs-HA composites were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). HA particles were generated on the surface of MWCNT. Produced MWCNTs-HA nanocomposites were coated on pure titanium (PT). Characteristic of the titanium coated MWCNTs-HA was evaluated by field-emission scanning electron microscopy (FE-SEM) and XRD. The results show that the titanium surface was covered with MWCNTs-HA nanoparticles and MWCNTs help form the crystalized hydroxyapatite. Furthermore, the MWCNTs-HA coated titanium was investigated for in vitro cellular responses. Cell proliferation and differentiation were improved on the surface of MWCNT-HA coated titanium.

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Synthesis, Characterization, and Microwave Absorption Properties of SrFe12O19 Ferrites and FeNi3 Nanoplatelets Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.148-149.893 ◽

2010 ◽

Vol 148-149 ◽

pp. 893-896 ◽

Cited By ~ 1

Author(s):

Ze Yang Zhang ◽

Xiang Xuan Liu ◽

You Peng Wu

Keyword(s):

Electron Microscopy ◽

Microwave Absorption ◽

Composite Coatings ◽

Sol Gel ◽

X Ray Diffraction ◽

Absorption Properties ◽

Filling Fraction ◽

Microwave Absorption Properties ◽

Phase Reduction ◽

Transmission Electron

M-typical SrFe12O19 ferrites and FeNi3 nanoplatelets were successfully prepared by the sol-gel method and solution phase reduction method, respectively. The crystalline and morphology of particles were studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The composite coatings with SrFe12O19 ferrites and FeNi3 nanoplatelets in polyvinylchloride matrix were prepared. The microwave absorption properties of these coatings were investigated in 2-18GHz frequency range. The results showed that the M-typical SrFe12O19 ferrites and FeNi3 nanoplatelets were obtained and they presented irregular sheet shapes. With the increase of the coating thickness, the absorbing peak value moves to the lower frequency. The absorbing peak values of the wave increase along with the increasing of the content of FeNi3 nanoplatelets filling fraction. When 40% SrFe12O19 ferrites is doped with 20% mass fraction FeNi3 nanoplatelets to prepare composite with 1.5mm thickness, the maximum reflection loss is -24.8 dB at 7.9GHz and the -10 dB bandwidth reaches 3.2GHz.

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