scholarly journals Synthesis of Novel Electrospun Composite Nano Powders of the Quaternary Ti-Al-O-B System

2020 ◽  
Author(s):  
Zohreh Ghadimi ◽  
Hamid Esfahani ◽  
Yousef Mazaheri
Keyword(s):  
Electron Microscope ◽  
Photoelectron Spectroscopy ◽  
Ceramic Powder ◽  
Simultaneous Thermal Analysis ◽  
Electrospun Nanofibers ◽  
Binding Energies ◽  
X Ray ◽  
Molar Ratios ◽  
Transmission Electron ◽  
Phase Study

Abstract In the present work, electrospinning was applied to develop multicomponent oxide, boride, and borate nanostructures in a quaternary Ti-Al-O-B system. Different molar ratios of B/(Ti + Al) (0.8, 1.6, and 2.4) were employed and evaluated. Imaging with the field emission scanning electron microscope (FESEM) and the transmission electron microscope (TEM) revealed that after one hour of thermal treatment at 1100 °C, the hybrid electrospun nanofibers (NFs) in the fibrous platform transformed into nanoparticles (NPs), nano-needles, and nano-whiskers at B/(Ti + Al) molar ratios of 0.8, 1.6, and 2.4, respectively. The binding energies were investigated by X-ray photoelectron spectroscopy (XPS), whereas the phase study was conducted via the X-ray diffraction (XRD) technique. The results confirmed the formation of nanostructured ceramic powder platforms composed of the multiple components, namely oxides (e.g., B doped TiO2; Al2O3), borides (TiB, TiB2, Ti2B5, TiB12, and AlB2), and borates (TiBO3; Al18B4O33). Simultaneous thermal analysis (STA) of the Ti-Al-O-B mats indicated that the borides and borates formed consecutively at temperatures above 800 °C through reactions involving molten B2O3. We found that the obtained NPs were well arranged and sintered together throughout the fibers.

scholarly journals Photocatalytic Degradation of Estriol Using Iron-Doped TiO2 under High and Low UV-Irradiation

2018 ◽  
Author(s):  
Irwing M. Ramírez-Sánchez ◽  
Erick R. Bandala
Keyword(s):  
Photocatalytic Activity ◽  
Electron Microscope ◽  
Uv Irradiation ◽  
Photoelectron Spectroscopy ◽  
Diffuse Reflectance Spectroscopy ◽  
Bet Surface Area ◽  
Doped Tio2 ◽  
X Ray ◽  
Transmission Electron ◽  
Iron Doped

Iron Doped TiO2 nanoparticles (Fe-TiO2) were synthesized and photocatalitically investigated under high and low fluence values of UV-radiation. The Fe-TiO2 physical characterization was performed using X-ray Powder Diffraction (XRD), Brunauer-Emmett-Teller (BET) surface area analysis, Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM), Diffuse Reflectance Spectroscopy (DRS), and X-Ray Photoelectron Spectroscopy (XPS) technique. The XPS evidenced that ferric ion (Fe3+) was in the lattice of TiO2 and co-dopants no intentionally added were also present due to the precursors of the synthetic method. The Fe3+ concentration played a key role in the photocatalytic generation of hydroxyl radical (•OH) and estriol (E3) degradation. Fe-TiO2 materials accomplished E3 degradation, and it was found that the catalyst with 0.3 at. % content of Fe (0.3 Fe-TiO2) enhanced the photocatalytic activity under low UV-irradiation compared with no intentionally Fe-added TiO2 (zero-iron TiO2) and Aeroxide® TiO2 P25. Furthermore, the enhanced photocatalytic activity of 0.3 Fe-TiO2 under low UV-irradiation may have applications when radiation intensity must be controlled, as in medical applications, or when strong UV absorbing species are present in water.

ZnFe2O4 Modified by Fe(NO3)3 for the Synthesis of Ionic Ferrofluids

2010 ◽  
Vol 177 ◽  
pp. 32-36 ◽  
Author(s):  
An Rong Wang ◽  
Jian Li ◽  
Qing Mei Zhang ◽  
Hua Miao
Keyword(s):  
Particle Size ◽  
Magnetic Properties ◽  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Photoelectron Spectroscopy ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Znfe2o4 Nanoparticles

Weak magnetic ZnFe2O4 nanoparticles were prepared by coprecipitation and treated with different concentrations of Fe(NO3)3 solution. Untreated and treated particles were studied using a vibrating sample magnetometer, transmission electron microscope, by X-ray diffraction, X-ray energy dispersive spectroscopy and X photoelectron spectroscopy. The results showed that, after treatment, the ZnFe2O4/γ-Fe2O3 forms disphase nanoparticles, with enlarged size, enhanced magnetic properties and with a surface parceled with Fe(NO3)3. The size of the particles and their magnetic properties are related to the concentration of the treatment solution. The particle size and magnetic properties could be controlled by controlling the concentration of treating solution, therefore nanoparticles can be more widely used.

scholarly journals Optimization of sol-immobilized bimetallic Au–Pd/TiO 2 catalysts: reduction of 4-nitrophenol to 4-aminophenol for wastewater remediation

2020 ◽  
Vol 378 (2176) ◽  
pp. 20200057
Author(s):  
Khaled Alshammari ◽  
Yubiao Niu ◽  
Richard E. Palmer ◽  
Nikolaos Dimitratos
Keyword(s):  
Photoelectron Spectroscopy ◽  
Catalytic Reduction ◽  
Catalytic Performance ◽  
Reducing Agent ◽  
Wastewater Remediation ◽  
X Ray ◽  
Molar Ratios ◽  
Highly Active ◽  
Transmission Electron ◽  
Complementary Techniques

A sol-immobilization method is used to synthesize a series of highly active and stable Au x Pd 1− x /TiO 2 catalysts (where x  = 0, 0.13, 0.25, 0.5, 0.75, 0.87 and 1) for wastewater remediation. The catalytic performance of the materials was evaluated for the catalytic reduction of 4-nitrophenol, a model wastewater contaminant, using NaBH 4 as the reducing agent under mild reaction conditions. Reaction parameters such as substrate/metal and substrate/reducing agent molar ratios, reaction temperature and stirring rate were investigated. Structure-activity correlations were studied using a number of complementary techniques including X-ray powder diffraction, X-ray photoelectron spectroscopy and transmission electron microscopy. The sol-immobilization route provides very small Au–Pd alloyed nanoparticles, with the highest catalytic performance shown by the Au 0.5 Pd 0.5 /TiO 2 catalyst. This article is part of a discussion meeting issue ‘Science to enable the circular economy’.

Preparation, Characterization and Tribological Evaluation of Calcium Borate Nanoparticles as Lubricant Additives

2010 ◽  
Vol 148-149 ◽  
pp. 1047-1056 ◽  
Author(s):  
Jiu Sheng Li ◽  
Li Feng Hao ◽  
Xiao Hong Xu ◽  
Li Zhang ◽  
Tian Hui Ren
Keyword(s):  
Oleic Acid ◽  
Electron Microscope ◽  
Photoelectron Spectroscopy ◽  
Lubricant Additive ◽  
Calcium Borate ◽  
Action Mechanism ◽  
Friction Process ◽  
X Ray ◽  
Transmission Electron ◽  
Worn Surface

To develop a potential substitute for conventional lubricant additive, pure calcium borate nanoparticles (PCBN) and calcium borate nanoparticles modified with oleic acid (MCBN) were prepared. The microstructures of the as-obtained samples were characterized using X-ray power diffraction (XRD), transmission electron microscope (TEM) and infrared spectra (IR), and the dispersing stability of oil containing nanoparticles was also evaluated. Tribological properties of MCBN used as lubricating additive were evaluated using four-ball tribometer and compared with that of PCBN. The results indicate that MCBN show better antiwear and friction-reducing property than PCBN. The worn surface of the steel ball lubricated with MCBN was investigated by Polarized microscope (PM) and X-ray photoelectron spectroscopy (XPS), and the action mechanism of MCBN during friction process was preliminarily discussed.

Gamma Irradiation Assisted Synthesis of Ag/rGO Composites and their Surface Properties

2017 ◽  
Vol 898 ◽  
pp. 2224-2230
Author(s):  
Ying Liang ◽  
Bin Fang ◽  
Fang Fang Lin ◽  
Xu Min Zhu
Keyword(s):  
Graphene Oxide ◽  
Electron Microscope ◽  
Gamma Irradiation ◽  
Surface Properties ◽  
Photoelectron Spectroscopy ◽  
Absorbed Dose ◽  
Silver Ions ◽  
Broad Absorption Band ◽  
X Ray ◽  
Transmission Electron

Ag/rGO composites were synthesized under gamma irradiation using silver nitrate and graphene oxide (GO) as the starting materials. Comparing with traditional methods, gamma irradiation is a simple and “green” technique. In the irradiation system, silver ions were reduced to silver nanoparticles (AgNPs) by the electrons generated from the radiolysis of solvent. GO nanosheets provided reactive sites for the formation of AgNPs and acted as a colloidal surfactant preventing the aggregation of AgNPs. Meanwhile, GO were partially reduced to reduced graphene oxide (rGO). X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscope, transmission electron microscope, Raman spectra and UV-Vis absorption spectra were applied for the characterization of Ag/rGO composites. The results showed that the absorbed dose (3.1 kGy, 4.7 kGy, 9.4 kGy and 27.4 kGy) plays an important role in the size distribution of AgNPs and the reduction degree of GO nanosheetes. The Ag/rGO composites exhibit a broad absorption band at visible light due to the surface plasmon resonance of AgNPs. Because of the unique surface properties, Ag/rGO composites behave enhanced performance for the adsorption of organic dye from water.

A study of the interaction of silver with amorphous chalcogenide films in the Scanning Electron Microscope

1990 ◽  
Vol 48 (4) ◽  
pp. 694-695
Author(s):  
A.G. Fitzgerald ◽  
S.M. Potrous
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Cross Sections ◽  
Photoelectron Spectroscopy ◽  
Depth Profiling ◽  
X Ray ◽  
Chalcogenide Films ◽  
Transmission Electron ◽  
Amorphous Chalcogenides ◽  
Scanning Electron

The diffusion of silver in amorphous chalcogenides is the basis for high-resolution lithographic applications. Previous studies of the diffusion of silver on contact with chalcogenide films has been studied by Auger depth profiling and the effects of photodoping on chemical bonding have been studied by x-ray photoelectron spectroscopy. Electron lithographic effects have been studied in the transmission electron microscope.The objective of the investigation described here has been to determine the degree of diffusion of silver in the amorphous chalcogenides, As2S3, As2Se3, GeS and GeSe when these films are in contact with thin silver films. The silver distribution has been determined by x-ray microanalysis of film cross-sections in the scanning electron microscope (SEM). Electron beam induced conductivity (EBIC) at points in these films has also been investigated.

Fabrication of g-C3N4/Y-TiO2 Z-scheme heterojunction photocatalysts for enhanced photocatalytic activity

2021 ◽  
Author(s):  
SongSik Pak ◽  
KwangChol Ri ◽  
Chenmin Xu ◽  
Qiuyi Ji ◽  
Dunyu Sun ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Fourier Transform ◽  
Photocatalytic Activity ◽  
Electron Microscope ◽  
Photoelectron Spectroscopy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

The g-C3N4/Y-TiO2 Z-scheme heterojunction photocatalysts were successfully synthesized. The powder X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscope, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy were used for...

scholarly journals A Fenton-Like Nanocatalyst Based on Easily Separated Magnetic Nanorings for Oxidation and Degradation of Dye Pollutant

Materials ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 332 ◽  
Author(s):  
Xiaonan Li ◽  
Jinghua Li ◽  
Weilu Shi ◽  
Jianfeng Bao ◽  
Xianyuan Yang
Keyword(s):  
Electron Microscope ◽  
Photoelectron Spectroscopy ◽  
Organic Dyes ◽  
Reaction Medium ◽  
Bromophenol Blue ◽  
Vibrating Sample Magnetometer ◽  
X Ray ◽  
Transmission Electron ◽  
Considerable Loss ◽  
Scanning Electron

In this study, uniform Fe3O4 magnetic nanorings (Fe3O4-MNRs) were prepared through a simple hydrothermal method. The morphology, magnetic properties, and structure of the product were characterized by transmission electron microscope (TEM), scanning electron microscope (SEM), high resolution transmission electron microscopy (HRTEM), vibrating sample magnetometer (VSM), X-ray powder diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), respectively. The Fe3O4-MNRs were used as Fenton-like catalysts in the presence of hydrogen peroxide (H2O2) and showed excellent Fenton-catalytic activity for degradation of organic dyes such as Methylene blue (MB), Rhodamine B (RhB), and Bromophenol blue (BPB). Furthermore, the obtained Fe3O4-MNRs could be recycled after used for several times and still remained in a relative high activity and could rapidly be separated from the reaction medium using a magnet without considerable loss. All results reveal that Fe3O4-MNRs have potential for the treatment of dyes pollutants.

Co(OH)2 ELECTROCATALYST DECORATED ON TiO2 FILM FOR ENHANCED PHOTOELECTROCATALYTIC WATER OXIDATION

2020 ◽  
Vol 27 (11) ◽  
pp. 2050003
Author(s):  
HONGXIA LI ◽  
CHAO YANG ◽  
JIAN ZHANG ◽  
XIANGUO LIU ◽  
XUEFENG ZHANG
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Water Splitting ◽  
Transmission Electron Microscope ◽  
Photoelectron Spectroscopy ◽  
Water Oxidation ◽  
Low Cost ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

Recently, Co(OH)2 has gained much attention as a promising electrocatalyst. Herein, we synthesized Co(OH)2-decorated TiO2 film for electrocatalytic water splitting by a facile and low-cost electrochemistry method, which possessed enhanced performance for oxygen evolution reaction. The results of X-ray diffractometry, transmission electron microscope, scanning electron microscope and X-ray photoelectron spectroscopy verify the successful decoration of Co(OH)2 electrocatalysts onto the surface of TiO2. Moreover, photoelectrocatalytic measurements illustrate that the Co(OH)2-decorated TiO2 shows higher current density than pure TiO2 sample. The results obtained in this work give deep insights into the development of photoelectrochemical water splitting.

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