Hydroxyapatite Biosynthesis Obtained from Sea Urchin Spines (Strongylocentrotus purpuratus): Effect of Synthesis Temperature

In this investigation, hydroxyapatite (HA) was synthesized using sea urchin spines (Strongylocentrotus purpuratus) via a precipitation and heat treatment method at three different temperatures (500, 600 and 700 °C). Biosynthesized HA was characterized to determine the vibration of functional groups, morphology, particle size, crystalline structure and chemical composition. For this, Fourier-Transform Infrared Spectroscopy with Attenuated Total Reflectance (FTIR-ATR), Scanning Electron Microscopy (SEM) coupled with Energy Dispersive X-ray Spectroscopy (EDS), X-ray Diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS) were used, respectively. The FTIR-ATR results reveal that the most defined characteristic HA bonds (O-H, P-O and C-O bonds) were better defined at higher synthesis temperatures. SEM also presented evidence that temperature has a significant effect on morphology. EDS results showed that the Ca/P ratio increased in the samples at higher temperatures. XRD analysis presented the characteristic peaks of HA, showing a lower crystallinity when the synthesis temperature increased. Finally, the XPS confirmed that the material resulting from biosynthesis was HA. Hence, according to these results, the synthesis temperature of HA has a significant effect on the characteristics of the resulting material.

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Non-Thermal Plasma-Modified Ru-Sn-Ti Catalyst for Chlorinated Volatile Organic Compound Degradation

Catalysts ◽

10.3390/catal10121456 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1456

Author(s):

Yujie Fu ◽

You Zhang ◽

Qi Xin ◽

Zhong Zheng ◽

Yu Zhang ◽

...

Keyword(s):

Plasma Treatment ◽

Photoelectron Spectroscopy ◽

High Surface ◽

High Surface Area ◽

Surface Oxidation ◽

Treatment Method ◽

X Ray ◽

Chlorinated Volatile Organic Compounds ◽

Volatile Organic ◽

Doped Titania

Chlorinated volatile organic compounds (CVOCs) are vital environmental concerns due to their low biodegradability and long-term persistence. Catalytic combustion technology is one of the more commonly used technologies for the treatment of CVOCs. Catalysts with high low-temperature activity, superior selectivity of non-toxic products, and resistance to chlorine poisoning are desirable. Here we adopted a plasma treatment method to synthesize a tin-doped titania loaded with ruthenium dioxide (RuO2) catalyst, possessing enhanced activity (T90%, the temperature at which 90% of dichloromethane (DCM) is decomposed, is 262 °C) compared to the catalyst prepared by the conventional calcination method. As revealed by transmission electron microscopy, X-ray diffraction, N2 adsorption, X-ray photoelectron spectroscopy, and hydrogen temperature-programmed reduction, the high surface area of the tin-doped titania catalyst and the enhanced dispersion and surface oxidation of RuO2 induced by plasma treatment were found to be the main factors determining excellent catalytic activities.

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Effect of calcination temperature on rare earth tailing catalysts for catalytic methane combustion

Green Processing and Synthesis ◽

10.1515/gps-2020-0053 ◽

2020 ◽

Vol 9 (1) ◽

pp. 734-743

Author(s):

Ran Zhao ◽

ZiChen Tian ◽

Zengwu Zhao

Keyword(s):

Rare Earth ◽

Mine Tailings ◽

Photoelectron Spectroscopy ◽

Methane Combustion ◽

Space Velocity ◽

High Catalytic Activity ◽

Reduction Peak ◽

X Ray ◽

Different Temperatures ◽

Bayan Obo

AbstractBayan Obo tailings are rich in rare earth elements (REEs), iron, and other catalytic active substances. In this study, mine tailings were calcined at different temperatures and tested for the catalytic combustion of low-concentration methane. Upon calcination at 600°C, high catalytic activity was revealed, with 50% CH4 conversion at 587°C (space velocity of 12,000 mL/g h). The physicochemical properties of catalysts were characterized using thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, hydrogen temperature-programmed reduction (H2-TPR), and X-ray photoelectron spectroscopy (XPS). Compared to the raw ore sample, the diffraction peak intensity of Fe2O3 increased post calcination, whereas that of CeCO3F decreased. A porous structure appeared after the catalyst was calcined at 600°C. Additionally, Fe, Ce, Ti, and other metal elements were more highly dispersed on the catalyst surface. H2-TPR results revealed a broadening of the reduction temperature range for the catalyst calcined at 600°C and an increase in the reduction peak. XPS analysis indicated the presence of Ce in the form of Ce3+ and Ce4+ oxidation states and the coexistence of Fe in the form of Fe2+ and Fe3+. Moreover, XPS revealed a higher surface Oads/Olatt ratio. This study provides evidence for the green reuse of Bayan Obo mine tailings in secondary resources.

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An Insight into Chemistry and Structure of Colloidal 2D-WS2 Nanoflakes: Combined XPS and XRD Study

Nanomaterials ◽

10.3390/nano11081969 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1969

Author(s):

Riccardo Scarfiello ◽

Elisabetta Mazzotta ◽

Davide Altamura ◽

Concetta Nobile ◽

Rosanna Mastria ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Xrd Analysis ◽

Crystal Habit ◽

Phase Identification ◽

X Ray Diffraction ◽

X Ray ◽

Morphological Evaluation ◽

Rational Understanding ◽

Structural Inspection

The surface and structural characterization techniques of three atom-thick bi-dimensional 2D-WS2 colloidal nanocrystals cross the limit of bulk investigation, offering the possibility of simultaneous phase identification, structural-to-morphological evaluation, and surface chemical description. In the present study, we report a rational understanding based on X-ray photoelectron spectroscopy (XPS) and structural inspection of two kinds of dimensionally controllable 2D-WS2 colloidal nanoflakes (NFLs) generated with a surfactant assisted non-hydrolytic route. The qualitative and quantitative determination of 1T’ and 2H phases based on W 4f XPS signal components, together with the presence of two kinds of sulfur ions, S22− and S2−, based on S 2p signal and related to the formation of WS2 and WOxSy in a mixed oxygen-sulfur environment, are carefully reported and discussed for both nanocrystals breeds. The XPS results are used as an input for detailed X-ray Diffraction (XRD) analysis allowing for a clear discrimination of NFLs crystal habit, and an estimation of the exact number of atomic monolayers composing the 2D-WS2 nanocrystalline samples.

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Deposition of Cobalt Doped Zinc Oxide Thin Film Nano-Composites Via Pulsed Electron Beam Ablation

MRS Advances ◽

10.1557/adv.2016.44 ◽

2016 ◽

Vol 1 (6) ◽

pp. 433-439 ◽

Cited By ~ 6

Author(s):

Asghar Ali ◽

Patrick Morrow ◽

Redhouane Henda ◽

Ragnar Fagerberg

Keyword(s):

Zinc Oxide ◽

Electron Beam ◽

Binding Energy ◽

Photoelectron Spectroscopy ◽

Xrd Analysis ◽

Sem Analysis ◽

Oxide Thin Film ◽

X Ray ◽

Pulsed Electron Beam ◽

Deposited Films

AbstractThis study reports on the preparation of cobalt doped zinc oxide (Co:ZnO) films via pulsed electron beam ablation (PEBA) from a single target containing 20 w% Co on sapphire (0001) and silicon (100) substrates. The films have been deposited at various temperatures (350оC, 400оC, 450оC) and pulse frequencies (2 Hz, 4 Hz), under a background argon (Ar) pressure of about 3 mtorr, and an accelerating voltage of 14 kV. The surface morphology has been examined by atomic force microscopy (AFM) and scanning electron microscopy (SEM). According to SEM analysis, the films consist of nano-globules whose size is in the range of 80-178 nm. Energy dispersive x-ray spectroscopy (EDX) reveals that deposition is congruent and the prepared films contain ∼20±5 w% cobalt. It has been found that the nano-globules in the deposited films are cobalt-rich zones containing ∼70 w% Co. From x-ray photoelectron spectroscopy (XPS) analysis, Co 2p3/2 peaks indicate that the deposited films contain CoO (binding energy = 780.5 eV) as well as metallic Co (binding energy = 778.1-778.5 eV). X-ray diffraction (XRD) analysis supports the presence of metallic Co hcp phase (2ϴ = 44.47° and 47.43°) in the films.

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Effect of Microstructural Characteristics of Electroless Nickel Metallisation on Solderability to Pb-Free Solder Alloys

Advances in Electronic Packaging, Parts A, B, and C ◽

10.1115/ipack2005-73160 ◽

2005 ◽

Author(s):

Changqing Liu ◽

David A. Hutt ◽

Dezhi Li ◽

Paul P. Conway

Keyword(s):

Photoelectron Spectroscopy ◽

Surface Composition ◽

Bulk Composition ◽

Industrial Process ◽

Surface Characteristics ◽

Electroless Nickel ◽

X Ray ◽

N2 Atmosphere ◽

Different Temperatures ◽

Free Solder

This paper aims to gain an insight into the correlation between the microstructure and surface composition of electroless Ni-P and its behaviour during soldering with Pb free alloys including Sn-3.8Ag-0.7Cu, Sn-3.5Ag and Sn-0.7Cu. Ni-P coatings with different P contents were produced through an industrial process on copper metal substrates. The surface morphology of these coatings was observed by Scanning Electron Microscopy (SEM) and the bulk composition was analyzed by means of Energy Dispersive X-ray analysis (EDX). The mechanical properties of the coatings were evaluated by nano-indentation testing under different maximum loads. However, to understand the behaviour of P in Ni-P coatings and deterioration of the coating surfaces during exposure to air, the surfaces of the coatings were also characterised by X-ray Photoelectron Spectroscopy (XPS) for storage at different temperatures. The dependence of the solderability of Ni-P coatings on the storage time and temperature was investigated by wetting balance testing, using an inactive or active flux with or without an inert N2 atmosphere. Finally, the solderability of Ni-P coatings to Pb free solders is correlated with their composition and microstructure (e.g. surface characteristics).

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GROWTH OF OXIDE LAYER ON GERMANIUM (011) SUBSTRATE UNDER DRY AND WET ATMOSPHERES

Surface Review and Letters ◽

10.1142/s0218625x99001141 ◽

1999 ◽

Vol 06 (06) ◽

pp. 1053-1060 ◽

Cited By ~ 11

Author(s):

N. TABET ◽

J. AL-SADAH ◽

M. SALIM

Keyword(s):

Simple Model ◽

Oxide Film ◽

Growth Kinetics ◽

Photoelectron Spectroscopy ◽

Early Stage ◽

X Ray ◽

Apparent Thickness ◽

Different Temperatures ◽

Kinetics Of

X-ray Photoelectron Spectroscopy (XPS) has been used to investigate the oxidation of (011) Ge substrates. The sample surfaces were CP4-etched, then annealed in situ, at different temperatures, for various durations. Dry and wet atmospheres were used. The oxidation rate during the early stage was increased by the presence of moisture in the atmosphere. A simple model was used to define and determine an apparent thickness of the oxide film from XPS measurements. The time dependence of the apparent thickness is consistent with a partial coverage of the surface by oxide islands. The growth kinetics of the oxide islands obeys a nearly cubic law.

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Preparation and Photocatalytic Performances of WO3/TiO2 Composite Nanofibers

Journal of Chemistry ◽

10.1155/2020/2390486 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12

Author(s):

Xiuping Han ◽

Binghua Yao ◽

Keying Li ◽

Wenjing Zhu ◽

Xuyuan Zhang

Keyword(s):

Photoelectron Spectroscopy ◽

Photocatalytic Oxidation ◽

Composite Nanofibers ◽

Photogenerated Electron ◽

Xrd Analysis ◽

Catalytic Performance ◽

Active Species ◽

X Ray ◽

Bet Analysis ◽

Electron Holes

The use of sunlight for photocatalytic oxidation is an ideal strategy, but it is limited by factors such as insufficient light absorption intensity of the photocatalyst and easy recombination of photogenerated electron holes. TiO2 is favored by researchers as an environment-friendly catalyst. In this paper, TiO2 is combined with WO3 to obtain a nanofiber with excellent catalytic performance under sunlight. The WO3/TiO2 composite nanofibers were synthesized by using the electrospinning method. The X-ray diffraction (XRD) analysis indicated that WO3 was successfully integrated onto the surface of TiO2. The photodegradation performance and photocurrent analysis of the prepared nanofibers showed that the addition of WO3 really improved the photocatalytic performance of TiO2 nanofibers, methylene blue (MB) degradation rate increased from 72% to 96%, and 5% was the optimal composite mole percentage of W to Ti. The scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectra (UV-Vis DRS), and Brunauer-Emmett-Teller (BET) analysis further characterized the properties of 5% WO3/TiO2 nanofibers. The H2 generation rate of 5% WO3/TiO2 nanofibers was 107.15 μmol·g−1·h−1, in comparison with that of TiO2 nanofibers (73.21 μmol·g−1·h−1) under the same condition. The 5% WO3/TiO2 produced ·OH under illumination, which played an important role in the MB degradation. Also, the enhanced photocatalytic mechanism was also proposed based on the detailed analysis of the band gap and the active species trapping experiment. The results indicated that the effective separation of Z-scheme photogenerated electron-hole pairs and transfer system constructed between TiO2 and WO3 endowed the excellent photocatalytic activity of 5% WO3/TiO2 nanofibers.

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Surface Band Structure Studies of Si Rich Reconstructions on 4H-SiC(1-100)

Materials Science Forum ◽

10.4028/www.scientific.net/msf.483-485.547 ◽

2005 ◽

Vol 483-485 ◽

pp. 547-550 ◽

Cited By ~ 4

Author(s):

Konstantin V. Emtsev ◽

Thomas Seyller ◽

Lothar Ley ◽

A. Tadich ◽

L. Broekman ◽

...

Keyword(s):

Electronic Structure ◽

Electron Diffraction ◽

Photoelectron Spectroscopy ◽

Low Energy ◽

Ultraviolet Photoelectron Spectroscopy ◽

Surface Band ◽

X Ray ◽

Low Energy Electron Diffraction ◽

Different Temperatures ◽

Low Energy Electron

We have investigated Si-rich reconstructions of 4H-SiC( 00 1 1 ) surfaces by means of low-energy electron diffraction (LEED), x-ray photoelectron spectroscopy (XPS), and angleresolved ultraviolet photoelectron spectroscopy (ARUPS). The reconstructions of 4H-SiC( 00 1 1 ) were prepared by annealing the sample at different temperatures in a flux of Si. Depending on the temperature different reconstructions were observed: c(2×2) at T=800°C, c(2×4) at T=840°C. Both reconstructions show strong similarities in the electronic structure.

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Fabrication of Nickel Sulfide/Nitrogen-Doped Reduced Graphene Oxide Nanocomposite as Anode Material for Lithium-Ion Batteries and Its Electrochemical Performance

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.18783 ◽

2020 ◽

Vol 20 (11) ◽

pp. 6782-6787

Author(s):

Yeon-Ju Lee ◽

Tae-Hyun Ha ◽

Gyu-Bong Cho ◽

Ki-Won Kim ◽

Jou-Hyeon Ahn ◽

...

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Photoelectron Spectroscopy ◽

Lithium Ion ◽

Treatment Method ◽

Retention Capacity ◽

Graphene Nanocomposites ◽

X Ray ◽

Nitrogen Doped ◽

Reduced Graphene

In this study, NiS/graphene nanocomposites were synthesized by simple heat treatment method of three graphene materials (graphene oxide (GO), reduced graphene oxide (rGO) and nitrogen-doped graphene oxide (N-rGO)) and NiS precursor. The morphology and crystal structure of NiS/graphene nanocomposites were characterized using field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Electrochemical properties were also investigated. NiS/graphene nanocomposites homogeneously wrapped by graphene materials have been successfully manufactured. Among the three nanocomposites, NiS/N-rGO nanocomposite exhibited the highest initial and retention capacity in discharge, respectively, of 1240 mAh/g and 467 mAh/g up to 100 cycles at 0.5 C.

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Preparation and Characterization of CdSe Nanoparticles Synthesized Using the Ultrasonic Irradiation

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.124-126.1229 ◽

2007 ◽

Vol 124-126 ◽

pp. 1229-1232 ◽

Cited By ~ 1

Author(s):

Myoung Seok Sung ◽

Yoon Bok Lee ◽

Yong Jin Kim ◽

Yang Do Kim

Keyword(s):

Ultrasonic Irradiation ◽

Photoelectron Spectroscopy ◽

Irradiation Time ◽

Xrd Analysis ◽

Cdse Nanoparticles ◽

X Ray Diffraction ◽

X Ray ◽

Surface Emission ◽

Transmission Electron ◽

Average Size

Cadmium selenide(CdSe) nanoparticles were prepared in the aqueous solution containing isopropyl alcohol by the ultrasonic irradiation at room temperature. The cadmium chloride (CdCl2) and sodium selenosulfate (Na2SeSO3) were used as the cadmium and selenium source, respectively. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), UV-Vis absorption spectra and PL spectra were used to characterize the CdSe nanoparticles. XRD analysis revealed the formation of cubic structure CdSe. TEM images showed aggregated CdSe nanoparticles with the size of nanometer scale. Average size of CdSe nanoparticles were about 3.9, 5.0 and 5.1nm with sonication time of 6, 30 and 40 minutes, respectively. The surface emission became less intensive and shifted to red with increasing irradiation time. This paper presents the effects of ultrasonic on the formation of CdSe nanoparticles and its characteristics.

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