scholarly journals Correlation of Morphology and In-Vitro Degradation Behavior of Spray Pyrolyzed Bioactive Glasses

Materials ◽  
2019 ◽  
Vol 12 (22) ◽  
pp. 3703 ◽  
Author(s):  
Fetene Fufa Bakare ◽  
Yu-Jen Chou ◽  
Yu-Hsuan Huang ◽  
Abadi Hadush Tesfay ◽  
Toshihiro Moriga ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Particle Morphology ◽  
Nitrogen Adsorption ◽  
Bone Tissue Regeneration ◽  
Degradation Behavior ◽  
Surface Areas ◽  
Transmission Electron ◽  
Spray Pyrolysis Process ◽  
Adsorption Desorption

Bioactive glass (BG) is considered to be one of the most remarkable materials in the field of bone tissue regeneration due to its superior bioactivity. In this study, both un-treated and polyethylene glycols (PEG)-treated BG particles were prepared using a spray pyrolysis process to study the correlation between particle morphology and degradation behavior. The phase compositions, surface morphologies, inner structures, and specific surface areas of all BG specimens were examined by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and nitrogen adsorption/desorption, respectively. Simulated body fluid (SBF) immersion evaluated the assessments of bioactivity and degradation behavior. The results demonstrate three particle morphologies of solid, porous, and hollow factors. The correlation between porosity, bioactivity, and degradation behavior was discussed.

Nanostructured oxides for energy storage applications in batteries and supercapacitors

2009 ◽  
Vol 81 (8) ◽  
pp. 1489-1498 ◽  
Author(s):  
Amreesh Chandra ◽  
Alexander J. Roberts ◽  
Eric Lam How Yee ◽  
Robert C. T. Slade
Keyword(s):  
Electron Microscopy ◽  
Energy Storage ◽  
Specific Capacitance ◽  
Electrode Materials ◽  
Particle Morphology ◽  
Hydrothermal Route ◽  
Conductivity Enhancement ◽  
Surface Areas ◽  
Transmission Electron

Nanostructured materials are extensively investigated for application in energy storage and power generation devices. This paper deals with the synthesis and characterization of nanomaterials based on oxides of vanadium and with their application as electrode materials for energy storage systems viz. supercapacitors. These nano-oxides have been synthesized using a hydrothermal route in the presence of templates: 1-hexadecylamine, Tweens and Brij types. Using templates during synthesis enables tailoring of the particle morphology and physical characteristics of synthesized powders. Broad X-ray diffraction peaks show the formation of nanoparticles, confirmed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) investigations. SEM studies show that a large range of nanostructures such as needles, fibers, particles, etc. can be synthesized. These particles have varying surface areas and electrical conductivity. Enhancement of surface area as much as seven times relative to surface areas of starting parent materials has been observed. These properties make such materials ideal candidates for application as electrode materials in supercapacitors. Assembly and characterization of supercapacitors based on electrodes containing these active nano-oxides are discussed. Specific capacitance of >100 F g–1 has been observed. The specific capacitance decreases with cycling: causes of this phenomenon are presented.

SYNTHESIS, CHARACTERIZATION AND THE APPLICABILITY OF β-CYCLODEXTRINS FUNCTIONALIZED MESOPOROUS SBA-15 MOLECULAR SIEVES

NANO ◽  
2013 ◽  
Vol 08 (05) ◽  
pp. 1350050
Author(s):  
MIN GUAN ◽  
HAI-PENG BI ◽  
ZUYUAN WANG ◽  
SHAOHUA BU ◽  
LING HUANG ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Molecular Sieves ◽  
Nitrogen Adsorption ◽  
X Ray Diffraction ◽  
X Ray ◽  
Adsorption Capacities ◽  
Transmission Electron ◽  
Potential Applications ◽  
Adsorption Desorption

Mesoporous silicas SBA-15 are modified with β-Cyclodextrins (β-CD) by simple grafting method. β-CD functionalized SBA-15 was characterized by Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), nitrogen adsorption–desorption measurements, thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). Furthermore, the applicability of it is investigated through studying the adsorption properties of clenbuterol. It showed better adsorption capacities of clenbuterol than pure SBA-15. β-CD functionalized SBA-15 material has the potential applications in the treatment of clenbuterol contamination in food and environment science.

scholarly journals Oxidative Coupling of Methane over Mn2O3-Na2WO4/SiC Catalysts

Catalysts ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 363
Author(s):  
Jieun Kim ◽  
La-Hee Park ◽  
Jeong-Myeong Ha ◽  
Eun Duck Park
Keyword(s):  
Electron Microscopy ◽  
High Temperatures ◽  
Oxidative Coupling ◽  
Exothermic Reaction ◽  
Nitrogen Adsorption ◽  
Catalytic Performance ◽  
Oxidative Coupling Of Methane ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Adsorption Desorption

The oxidative coupling of methane (OCM) is operated at high temperatures and is a highly exothermic reaction; thus, hotspots form on the catalyst surface during reaction unless the produced heat is removed. It is crucial to control the heat formed because surface hotspots can degrade catalytic performance. Herein, we report the preparation of Mn2O3-Na2WO4/SiC catalysts using SiC, which has high thermal conductivity and good stability at high temperatures, and the catalyst was applied to the OCM. Two Mn2O3-Na2WO4/SiC catalysts were prepared by wet-impregnation on SiC supports having different particle sizes. For comparison, the Mn2O3-Na2WO4/SiO2 catalyst was also prepared by the same method. The catalysts were analyzed by nitrogen adsorption–desorption, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The transformation of SiC into α-cristobalite was observed for the Mn2O3-Na2WO4/SiC catalysts. Because SiC was completely converted into α-cristobalite for the nano-sized SiC-supported Mn2O3-Na2WO4 catalyst, the catalytic performance for the OCM reaction of Mn2O3-Na2WO4/n-SiC was similar to that of Mn2O3-Na2WO4/SiO2. However, only the surface layer of SiC was transformed into α-cristobalite for the micro-sized SiC (m-SiC) in Mn2O3-Na2WO4/m-SiC, resulting in a SiC@α-cristobalite core–shell structure. The Mn2O3-Na2WO4/m-SiC showed higher methane conversion and C2+ yield at 800 and 850 °C than Mn2O3-Na2WO4/SiO2.

scholarly journals SYNTHESIS AND ELECTROCHEMICAL PROPERTIES OF MESOPOROUS CARBON SUPPORTED WELL–DISPERSED COBALT OXIDES NANOPARTICLES

2018 ◽  
Vol 55 (1B) ◽  
pp. 230
Author(s):  
Nguyen Van Tu
Keyword(s):  
Electron Microscopy ◽  
Cobalt Oxide ◽  
Mesoporous Carbon ◽  
Good Control ◽  
Nitrogen Adsorption ◽  
Mesoporous Structure ◽  
Oxide Nanoparticles ◽  
Cobalt Oxide Nanoparticles ◽  
Transmission Electron ◽  
Adsorption Desorption

In this article, well–dispersed cobalt oxide nanoparticles supported on mesoporous carbon (CMK–3) have been successfully synthesized. The composites were characterized by field emission scanning electron microscopy, transmission electron microscopy, X–ray diffraction and nitrogen adsorption–desorption analysis. The results have confirmed that, at a cobalt loading of 15 wt%, the composites have not only retained mesoporous structure of the support but also shown a good control of dispersed cobalt oxide nanoparticles with size of ~4 nm. The electrochemical property tests for the synthesized samples have shown significant improvement compared to the blank carbon (CMK–3) without cobalt oxide incorporation.

The Photocatalysis Properties of Heterostructured WO3-TiO2 Composite Prepared by Waste WC-TiC Hardmetal

2013 ◽  
Vol 873 ◽  
pp. 603-611
Author(s):  
Yi Long Yang ◽  
Jin Shu Wang ◽  
Yong Li Li ◽  
Jun Shu Wu ◽  
Hong Yi Li
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Critical Role ◽  
Nitrogen Adsorption ◽  
Light Illumination ◽  
Hydrothermal Route ◽  
Transmission Electron ◽  
Facile Hydrothermal Route ◽  
Vis Spectroscopy ◽  
Adsorption Desorption

We reported a facile hydrothermal route for the preparation of WO3TiO2 composite nanoparticles (TWCNs) using waste WC-TiC hardmetal in the presence of hydrofluoric acid (HF). Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and nitrogen adsorption/desorption analysis were employed for structural and composition analyses of the TWCNs. Our results suggested that HF was not only strongly involved in the growth of WO3, but also played a critical role in the etching effect for TWCN product. The photocatalytic activity of TWCNs was investigated by UV-vis spectroscopy. Dye molecules could be rapidly decomposed with TWCNs photocatalyst under visible light illumination. The enhanced photocatalytic activity is attributed to well matched band edge positions of WO3 and TiO2, and the large specific surface area of TWCNs in view of the incorporation of mesopores. The results presented here are expected to make a contribution toward the development of recycling waste resource delicately for photocatalytic water purification.

scholarly journals Photocatalytic properties of Ru-doped titania prepared by homogeneous hydrolysis

2009 ◽  
Vol 7 (2) ◽  
pp. 259-266 ◽  
Author(s):  
Vendula Houšková ◽  
Václav Štengl ◽  
Snejana Bakardjieva ◽  
Nataliya Murafa ◽  
Václav Tyrpekl
Keyword(s):  
Electron Microscopy ◽  
Ruthenium Oxide ◽  
Nitrogen Adsorption ◽  
Photocatalytic Decomposition ◽  
X Ray Diffraction ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron ◽  
Doped Titania ◽  
Adsorption Desorption ◽  
Hydrolysis Of

AbstractNanocrystalline titania particles doped with ruthenium oxide have been prepared by the homogenous hydrolysis of TiOSO4 in aqueous solutions in the presence of urea. The synthesized particles were characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), High Resolution Transmission Electron Microscopy (HRTEM), Selected Area Electron Diffraction (SAED) and Nitrogen adsorption-desorption was used for surface area (BET) and porosity determination (BJH). The photocatalytic activity of the Ru-doped titania samples were determined by photocatalytic decomposition of Orange II dye in an aqueous slurry during irradiation at 365 nm and 400 nm wavelengths.

scholarly journals Sonochemical Synthesis, Characterization, and Photocatalytic Activity of N-Doped TiO2Nanocrystals with Mesoporous Structure

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Tiekun Jia ◽  
Fang Fu ◽  
Junwei Zhao ◽  
Jian Chen ◽  
Xiaofeng Wang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Visible Region ◽  
Nitrogen Adsorption ◽  
Mesoporous Structure ◽  
Diffuse Reflection Spectroscopy ◽  
X Ray ◽  
Transmission Electron ◽  
Average Size ◽  
Adsorption Desorption

N-Doped TiO2nanocrystals were synthesized via a simple sonochemical route, using titanium tetrachloride, aqueous ammonia, and urea as starting materials. The as-synthesized samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) equipped with an energy dispersion X-ray spectrometer (EDS), transmission electron microscopy (TEM), UV-vis diffuse reflection spectroscopy, Raman spectroscopy, and nitrogen adsorption-desorption isotherms. The results of TEM and nitrogen adsorption-desorption showed that the average size and specific surface area of the as-synthesized nanocrystals are 10 nm and 107.2 m2/g, respectively. Raman spectral characterization combined with the results of XRD and EDS revealed that N dopant ions were successfully doped into TiO2. Compared with pure TiO2, the adsorption band edge of N-doped TiO2samples exhibited an obvious red shift to visible region. The photocatalytic activities were evaluated by the degradation of Rhodamine B (RhB) under visible light, and the results showed that the N-doped TiO2sample synthesized by an optimal amount of urea exhibited excellent photocatalytic activity due to its special mesoporous structure and the incorporation of nitrogen dopant ions.

scholarly journals An Investigation on Spray-Granulated, Macroporous, Bioactive Glass Microspheres for a Controlled Drug Delivery System

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3112
Author(s):  
Henni Setia Ningsih ◽  
Liu-Gu Chen ◽  
Ren-Jei Chung ◽  
Yu-Jen Chou
Keyword(s):  
Drug Release ◽  
Bioactive Glass ◽  
Particle Morphology ◽  
Nitrogen Adsorption ◽  
Drug Carriers ◽  
In Vitro Drug Release ◽  
Controlled Drug Delivery System ◽  
Excellent Candidate ◽  
Adsorption Desorption

Bioactive glass (BG) has been regarded as an excellent candidate for biomedical applications due to its superior properties of bioactivity, biocompatibility, osteoconductivity and biodegradability. Thus, in this study, we aimed to fabricate drug carriers that were capable of loading therapeutic antibiotics while promoting bone regeneration using macroporous BG microspheres, prepared by a spray drying method. Characterizations of particle morphology and specific surface area were carried out via scanning electron microscopy and nitrogen adsorption/desorption isotherm. Evaluations of in vitro bioactivity were performed based on Kokubo’s simulated body fluid to confirm the formation of the hydroxyapatite (HA) layer after immersion. In addition, the in vitro drug release behaviors were examined, using tetracycline as the therapeutic antibiotic in pH 7.4 and 5.0 environments. Finally, the results showed that BG microspheres of up to 33 μm could be mass-produced, targeting various therapeutic situations and their resulting bioactivities and drug release behaviors, and related properties were discussed.

Heterogenization of manganese porphyrin via hydrogen bond in zeolite imidazolate framework-8 matrix, a host–guest interaction, as catalytic system for olefin epoxidation

2018 ◽  
Vol 22 (11) ◽  
pp. 972-980 ◽  
Author(s):  
Mojtaba Bagherzadeh ◽  
Elnaz Mesbahi
Keyword(s):  
Electron Microscopy ◽  
Hydrogen Bond ◽  
Catalytic System ◽  
Nitrogen Adsorption ◽  
Olefin Epoxidation ◽  
Manganese Porphyrin ◽  
Transmission Electron ◽  
Classical Hydrogen Bond ◽  
Ft Ir ◽  
Adsorption Desorption

A heterogenized meso-tetrakis(2,3-dihydroxyphenyl)porphyrinatomanganese(III) acetate at zeolite imidazolate framework-8 (T(2,3-OHP)PorMn@ZIF-8) is investigated for the catalytic olefin epoxidation reactions at room temperature. Heterogenization is accomplished through a non-classical hydrogen bond proposed between T(2,3-OHP)PorMn bearing O–H groups and C–H of the 2-methylimidazolate linkers in the ZIF-8 structure. The aforementioned compound is characterized by X-ray powder diffraction (XRD), atomic absorption spectroscopy (AAS), nitrogen adsorption−desorption, FT-IR spectroscopy, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and Raman spectroscopy. The catalytic system with rather high potential of reusability is proposed as a fairly efficient epoxidation catalyst compared to reports in homogeneous media.

Synthesis of Flower-Like Mesoporous γ-AlOOH and γ-Al2O3 Nanoarchitectures via an Ionic Liquid-Assisted Hydrothermal Route

NANO ◽  
2019 ◽  
Vol 14 (04) ◽  
pp. 1950046
Author(s):  
Tong Il Kim ◽  
Hak Sung Yun ◽  
Yung Jon ◽  
Gwang Bok Han ◽  
Sung Il Chae ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Ionic Liquid ◽  
Hydrothermal Reaction ◽  
Hydrothermal Process ◽  
Reaction System ◽  
Nitrogen Adsorption ◽  
X Ray Diffraction ◽  
Hydrothermal Route ◽  
Transmission Electron ◽  
Adsorption Desorption

In this work, flower-like [Formula: see text]-AlOOH and [Formula: see text]-Al2O3 nanoarchitectures with excellent surface and mesoporous properties were successfully synthesized in ionic liquid-assisted hydrothermal reaction system. The as-prepared suprastructures were characterized by several techniques, such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption/desorption measurement. The formation mechanism of flower-like [Formula: see text]-AlOOH mesoporous crystallites by ionic liquid-assisted hydrothermal process was proposed and discussed. Flower-like [Formula: see text]-Al2O3 nanostructures were obtained by calcining the as-prepared [Formula: see text]-AlOOH at 600∘C for 2[Formula: see text]h, preserving the same morphology.

Sign in / Sign up

Export Citation Format

Share Document