Ultrafast Synthesis of Urchin-Like Rutile TiO2 by Single-Step Microwave-Assisted Method

The preparations of crystal titanium dioxide (TiO2) are often time-consuming multistep processes involving high temperature. Rapid and efficient methods to obtain TiO2 with anatase or rutile phase are desirable. In this paper, we describe an ultrafast single-step method to obtain urchin-like rutile TiO2 particles via microwave irradiation. In the procedure, TiCl4 aqueous solution was used as a reactant and toluene was used as a solvent. It takes only a few minutes without any further heat treatment. The samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and thermal gravimetric analysis (TGA). The effect of temperature, irradiation time and the ratio of precursor to solvent on the morphology and crystal structure were studied. The results show urchin-like rutile TiO2 with high stability is formed after only 5 min microwave irradiation at 135 °C.

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Characterization of Nanoscaled TiO2 Produced by Simplified Sol–Gel Method Using Organometallic Precursor

Journal of Engineering Materials and Technology ◽

10.1115/1.4029112 ◽

2015 ◽

Vol 137 (2) ◽

Cited By ~ 6

Author(s):

Perica Paunović ◽

Anita Grozdanov ◽

Andrej Češnovar ◽

Petre Makreski ◽

Gennaro Gentile ◽

...

Keyword(s):

Electron Microscopy ◽

Thermal Treatment ◽

Sol Gel ◽

Rutile Phase ◽

Gravimetric Analysis ◽

Titanium Tetraisopropoxide ◽

Gel Method ◽

Sol Gel Method ◽

Organometallic Precursor ◽

Transmission Electron

This work is concerned with development of sol–gel method for preparation of nanoscaled TiO2 using organometallic precursor—titanium tetraisopropoxide (TTIP) and determination of the present crystalline phases depending on the temperature of further thermal treatment. The characteristic processes and transformations during the thermal treatment were determined by means of thermal gravimetric analysis and/or differential thermal analysis (TGA/DTA) method. The crystalline structure and size of the TiO2 crystallites were analyzed by means of Raman spectroscopy and X-ray powder diffraction (XRPD) method. At 250 °C, cryptocrystalline structure was detected, where amorphous TiO2 is accompanied with crystalline anatase. The anatase crystallite phase is stable up to 650 °C, whereas at higher temperature rutile transformation begins. It was observed that at 800 °C, almost the whole TiO2 is transformed to rutile phase. According to XRPD analysis, the increase of the temperature influences on the increase of the size of the crystalline particles ranging from 6 nm at 250 °C to less than 100 nm at 800 °C. The size and shape of the TiO2 crystalline particles were observed by transmission electron microscopy (TEM). The shape of the studied samples changes from nanospheres (250, 380, and 550 °C) to nanorods (650 and 800 °C). Morphology of the formed TiO2 aggregates was observed by scanning electron microscopy (SEM).

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SYNTHESIS AND CHARACTERIZATION OF Ba2SmSbO6 NANOPARTICLES

Modern Physics Letters B ◽

10.1142/s0217984907013420 ◽

2007 ◽

Vol 21 (19) ◽

pp. 1227-1234 ◽

Cited By ~ 3

Author(s):

C. VIJAYAKUMAR ◽

H. PADMA KUMAR ◽

JIJIMON K. THOMAS ◽

SAM SOLOMON ◽

S. U. K. NAIR ◽

...

Keyword(s):

Electron Microscopy ◽

Thermo Gravimetric Analysis ◽

Combustion Process ◽

Single Step ◽

Gravimetric Analysis ◽

Prepared Powder ◽

Auto Ignition ◽

Transmission Electron ◽

Calcination Step ◽

Phase Pure

Nanoparticles of samarium barium antimonate ( Ba 2 SmSbO 6), a complex perovskite has been synthesized using an auto-ignition combustion process for the first time. The nanoparticles thus obtained have been characterized using X-ray diffraction, thermo-gravimetric analysis, differential thermal analysis, Fourier transform infrared spectroscopy, scanning electron microscopy and transmission electron microscopy. The XRD studies have shown that the as-prepared powder is phase pure Ba 2 SmSbO 6 and has a complex cubic perovskite ( A 2 BB ' O 6) crystalline structure with lattice constant a = 8.491 Å. The particle size of the as-prepared powder was in the range 20–50 nm. The nano crystals of Ba 2 SmSbO 6 synthesized by the combustion technique could be sintered to 97% of the theoretical density by heating at a temperature of 1550°C for 2 h. By the present combustion synthesis a phase pure Ba 2 SmSbO 6 nanopowder could be obtained by a single step process without the need of any calcination step.

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Green synthesis of stable Fe,Cu oxide nanocomposites from loquat leaf extracts for removal of Norfloxacin and Ciprofloxacin

Water Science & Technology ◽

10.2166/wst.2020.152 ◽

2020 ◽

Vol 81 (4) ◽

pp. 694-708

Author(s):

Qiujie Liu ◽

Peili Ma ◽

Penglei Liu ◽

Hongping Li ◽

Xiuli Han ◽

...

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Single Step ◽

Synthesis Methods ◽

X Ray Diffraction ◽

Step Method ◽

Leaf Extracts ◽

X Ray ◽

Transmission Electron ◽

Equilibrium Data

Abstract Mass production of nanomaterials to remove pollutants from water still faces many challenges, mainly due to the complexity of the synthesis methods involved and the use of dangerous reagents. The green method of preparation of nanomaterials from plants can effectively solve these problems. Fe,Cu oxide nanocomposites (Fe-Cu-NCs) were synthesized by a green and single-step method using loquat leaf extracts, and were used as an adsorbent for removal of Norfloxacin (NOR) and Ciprofloxacin (CIP) from aqueous solution. The synthesized adsorbent showed excellent adsorption properties for NOR and CIP. The experimental equilibrium data fitted the Redlich-Peterson and Koble-Corrigan models well and the maximum adsorption capacities of Fe-Cu-NCs calculated by the Langmuir model for NOR and CIP were 1.182 mmol/g and 1.103 mmol/g, respectively, at 293 K. Additionally, the morphologies and properties of Fe-Cu-NCs were characterized by transmission electron microscopy (TEM), scanning electron microscopy X-ray energy-dispersive spectroscopy (SEM-EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analysis and the adsorption mechanism of NOR and CIP onto Fe-Cu-NCs was discussed. Thermodynamic parameters revealed that the adsorption process was spontaneous and endothermic. This study indicated that Fe-Cu-NCs are a potential adsorbent and provide a simple and convenient strategy for the purification of antibiotics-laden wastewater.

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Nucleation of Disorder in Fe3Al Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061574 ◽

1967 ◽

Vol 25 ◽

pp. 312-313

Author(s):

P. R. Swann ◽

W. R. Duff ◽

R. M. Fisher

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Annealing Temperature ◽

Antiphase Domain ◽

Effect Of Temperature ◽

Domain Structures ◽

Transmission Electron ◽

Domain Boundaries ◽

Higher Temperature ◽

The One

Recently we have investigated the phase equilibria and antiphase domain structures of Fe-Al alloys containing from 18 to 50 at.% Al by transmission electron microscopy and Mössbauer techniques. This study has revealed that none of the published phase diagrams are correct, although the one proposed by Rimlinger agrees most closely with our results to be published separately. In this paper observations by transmission electron microscopy relating to the nucleation of disorder in Fe-24% Al will be described. Figure 1 shows the structure after heating this alloy to 776.6°C and quenching. The white areas are B2 micro-domains corresponding to regions of disorder which form at the annealing temperature and re-order during the quench. By examining specimens heated in a temperature gradient of 2°C/cm it is possible to determine the effect of temperature on the disordering reaction very precisely. It was found that disorder begins at existing antiphase domain boundaries but that at a slightly higher temperature (1°C) it also occurs by homogeneous nucleation within the domains. A small (∼ .01°C) further increase in temperature caused these micro-domains to completely fill the specimen.

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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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Enhanced Photocatalytic Activity of Cu2O Cabbage/RGO Nanocomposites under Visible Light Irradiation

Polymers ◽

10.3390/polym13111712 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1712

Author(s):

Appusamy Muthukrishnaraj ◽

Salma Ahmed Al-Zahrani ◽

Ahmed Al Otaibi ◽

Semmedu Selvaraj Kalaivani ◽

Ayyar Manikandan ◽

...

Keyword(s):

Electron Microscopy ◽

Thermo Gravimetric Analysis ◽

Visible Region ◽

Catalytic Performance ◽

Precipitation Method ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Dye Pollutants ◽

Transmission Electron

Towards the utilization of Cu2O nanomaterial for the degradation of industrial dye pollutants such as methylene blue and methyl orange, the graphene-incorporated Cu2O nanocomposites (GCC) were developed via a precipitation method. Using Hummers method, the grapheme oxide (GO) was initially synthesized. The varying weight percentages (1–4 wt %) of GO was incorporated along with the precipitation of Cu2O catalyst. Various characterization techniques such as Fourier-transform infra-red (FT-IR), X-ray diffraction (XRD), UV–visible diffused reflectance (UV-DRS), Raman spectroscopy, thermo gravimetric analysis (TGA), energy-dispersive X-ray analysis (EDX), and electro chemical impedance (EIS) were followed for characterization. The cabbage-like morphology of the developed Cu2O and its composites were ascertained from field-emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HR-TEM). In addition, the growth mechanism was also proposed. The results infer that 2 wt % GO-incorporated Cu2O composites shows the highest value of degradation efficiency (97.9% and 96.1%) for MB and MO at 160 and 220 min, respectively. Further, its catalytic performance over visible region (red shift) was also enhanced to an appreciable extent, when compared with that of other samples.

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Carbon Nanotubes Grown on Metallic Wires by Cold Plasma Technique

MRS Proceedings ◽

10.1557/proc-737-f3.44 ◽

2002 ◽

Vol 737 ◽

Author(s):

D. Sarangi ◽

A. Karimi

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Growth Conditions ◽

Effect Of Temperature ◽

Rutherford Back Scattering ◽

Novel Approach ◽

Transmission Electron ◽

Back Scattering ◽

Metallic Wires ◽

Metal Wires

ABSTRACTCarbon nanotubes on metallic wires may be act as electrode for the field emission (FE) luminescent devices. Growing nanotubes on metallic wires with controlled density, length and alignment are challenging issues for this kind of devices. We, in the present investigation grow carbon nanotubes directly on the metal wires by a powerful but simple technique. A novel approach has been proposed to align nanotubes during growth. Methane, acetylene and dimethylamine have been used as source gases. With the same growth conditions (viz. pressure, growth temperature and plasma) methane does not produce any nanotube but nanotubes grown with dimethylamine show shorter length and radius than acetylene. The effect of temperature to control the radius, time to control the density, plasma conditions to align the nanotubes has been focused. Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Rutherford Back Scattering (RBS) are used to characterize the nanotubes.

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Synthesis and Luminescence Properties of Tris (8-Hydroxyquinoline) Iron Spindle-Like Structures at Room Temperature

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.391-392.225 ◽

2011 ◽

Vol 391-392 ◽

pp. 225-229 ◽

Cited By ~ 1

Author(s):

Qing Hong Kong ◽

Hong Liu ◽

Yun Long Zhang ◽

Yong Sheng Yan

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Blue Shift ◽

Solvent System ◽

Iron Complex ◽

Molecular Formula ◽

Gravimetric Analysis ◽

Element Analysis ◽

Transmission Electron ◽

Fourier Transformation Infrared Spectroscopy

Spindle-like bis (8-hydroxyquinoline) iron (FeQ3) complex has been synthesized with a facile method in a mixed solvent system at room temperature for 12 h. The molecular formula of the products is speculated by the C, H and N element analysis and thermal gravimetric analysis, and Fourier-transformation infrared spectroscopy was also utilized to measure its structure, which further confirm the molecular formula of the products. The observation of field emission scanning electron microscopy and transmission electron microscopy shows that the morphology of tris (8-hydroxyquinoline) iron complex is spindle-like structure. The photoluminescence of the products were also investigated. The results indicate that the photoluminescence emission of FeQ3spindles shows obvious blue shift contrasted with that of 8-hydroxyquinoline.

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In Situ High-Temperature Transmission Electron Microscopy Observations of the Formation of Nanocrystalline TiC from Nanocrystalline Anatase (TiO2)

Microscopy and Microanalysis ◽

10.1017/s1431927698980278 ◽

1998 ◽

Vol 4 (3) ◽

pp. 269-277 ◽

Cited By ~ 8

Author(s):

A. Agrawal ◽

J. Cizeron ◽

V.L. Colvin

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

High Temperature ◽

Solid Phase ◽

Anatase Phase ◽

High Resolution Electron Microscopy ◽

Rutile Phase ◽

Transmission Electron ◽

New Phase

In this work, the high-temperature behavior of nanocrystalline TiO2 is studied using in situ transmission electron microscopy (TEM). These nanoparticles are made using wet chemical techniques that generate the anatase phase of TiO2 with average grain sizes of 6 nm. X-ray diffraction studies of nanophase TiO2 indicate the material undergoes a solid-solid phase transformation to the stable rutile phase between 600° and 900°C. This phase transition is not observed in the TEM samples, which remain anatase up to temperatures as high as 1000°C. Above 1000°C, nanoparticles become mobile on the amorphous carbon grid and by 1300°C, all anatase diffraction is lost and larger (50 nm) single crystals of a new phase are present. This new phase is identified as TiC both from high-resolution electron microscopy after heat treatment and electron diffraction collected during in situ heating experiments. Video images of the particle motion in situ show the nanoparticles diffusing and interacting with the underlying grid material as the reaction from TiO2 to TiC proceeds.

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Effect of Synthesis Temperature on Particles Size and Morphology of Zirconium Oxide Nanoparticle

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.50.18 ◽

2017 ◽

Vol 50 ◽

pp. 18-31 ◽

Cited By ~ 6

Author(s):

Rudzani Sigwadi ◽

Simon Dhlamini ◽

Touhami Mokrani ◽

Patrick Nonjola

Keyword(s):

Electron Microscopy ◽

Particle Size ◽

Zirconium Oxide ◽

Thermo Gravimetric Analysis ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Crystallite Sizes ◽

Ft Ir

The paper presents the synthesis and investigation of zirconium oxide (ZrO2) nanoparticles that were synthesised by precipitation method with the effects of the temperatures of reaction on the particles size, morphology, crystallite sizes and stability at high temperature. The reaction temperature effect on the particle size, morphology, crystallite sizes and stabilized a higher temperature (tetragonal and cubic) phases was studied. Thermal decomposition, band structure and functional groups were analyzed by Brunauer-Emmett-Teller (BET), Scanning Electron Microscopy (SEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), Thermo-gravimetric analysis (TGA) and Fourier transform infrared (FT-IR). The crystal structure was determined using X-ray diffraction. The morphology and the particle size were studied using (SEM) and (TEM). The shaped particles were confirmed through the SEM analysis. The transmission electron microscopic analysis confirmed the formation of the nanoparticles with the particle size. The FT-IR spectra showed the strong presence of ZrO2 nanoparticles.

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