scholarly journals Thermal Stability of Oxide-Based Solar Selective Coatings for CSP Central Receivers

2015 ◽  
Author(s):  
Andrea Ambrosini ◽  
Timothy N. Lambert ◽  
Antoine Boubault ◽  
Andrew Hunt ◽  
Danae J. Davis ◽  
...  
Keyword(s):  
Optical Properties ◽  
Morphological Changes ◽  
Morphological Properties ◽  
Inconel 625 ◽  
X Ray Diffraction ◽  
Haynes 230 ◽  
X Ray ◽  
Ni Alloys ◽  
Sprayed Coating ◽  
Thermal Stability Of

Efforts at Sandia National Laboratories are addressing more efficient solar selective coatings for tower applications, based on oxide materials deposited by a variety of methods. Over the course of this investigation, several compositions with optical properties competitive to Pyromark have been identified. These promising coatings were deposited on Inconel 625 and Haynes 230 Ni alloys and isothermally aged in air at temperatures between 600–800 °C for up to 480 hours, concurrently with Pyromark®, which was used as a reference standard. At various heating times, the samples were removed from the furnace and their optical properties (solar-weighted absorptance and emittance) were measured. In addition, x-ray diffraction and scanning electron microscopy were utilized to investigate any structural or morphological changes that occurred over time with heating, in an attempt to correlate with changes in optical properties. At 600 and 700 °C, several of the coatings maintained an absorptivity > 90%. While the chemical makeup of the coating material greatly influences its optical properties, the morphology of the surface also plays in important part. A thermal sprayed coating modified using a novel laser treatment showed improved properties versus the untreated coating, on par with Pyromark™ at 600 °C, with little degradation after 480 hours. The results of aging on the optical, structural, and morphological properties of these novel coatings will be discussed.

Properties of Montmorillonite-Reinforced Thermoplastic Sago Starch Composites

2012 ◽  
Vol 445 ◽  
pp. 469-474 ◽  
Author(s):  
Ahmad Zuraida ◽  
Y. Yusliza ◽  
O. Nurizan ◽  
H. Anuar ◽  
Zahurin Halim ◽  
...  
Keyword(s):  
Morphological Properties ◽  
Wave Number ◽  
Hydroxyl Groups ◽  
Sago Starch ◽  
X Ray Diffraction ◽  
Pressing Method ◽  
X Ray ◽  
Ft Ir ◽  
Thermal Stability Of ◽  
Better Than

In this work, biodegradable polymer was prepared from thermoplastic sago starch (TPSS) plasticized with glycerol. In order to improve the properties of the TPSS, Montmorillonite (MMT), a kind of reinforced additive was used in the preparation of montmorillonite-reinforced thermoplastic sago starch (MTRSS) composites via hot pressing method. The fabricated samples were investigated through X-ray diffractometry, Fourier transform infrared (FT-IR) as well as thermal and morphological properties. FT-IR patterns show that in the MTRSS composites, the C-O groups of sago starch molecules shifted to higher wave number, while the reactive hydroxyl groups of MMT shifted to the lower wavenumber. On the other hand, X-ray diffraction revealed that MMT restrained the crystallization of MTRSS and intercalated in TPSS. Thermogravimetric analysis (TGA) revealed that the thermal stability of MTRSS was better than those of TPSS. In addition, the scanning electron micrograph results show that MMT were uniformly dispersed in the TPSS.

scholarly journals Structural and Optical Properties of ZnO Nanorods Thin Films Prepared Using Hydrothermal Technique and Effect of growth time

2020 ◽  
Vol 12 (02) ◽  
pp. 76-88
Author(s):  
Ahmed S. Abed ◽  
◽  
Sattar J. Qasim ◽  
Abbas F. Abbas ◽  
Keyword(s):  
Optical Properties ◽  
Zno Nanorods ◽  
Band Gap Energy ◽  
Zinc Oxide Nanorods ◽  
Morphological Properties ◽  
Growth Time ◽  
X Ray Diffraction ◽  
Hydrothermal Technique ◽  
X Ray ◽  
Oxide Nanorods

This paper describes, Synthesis of zinc oxide nanorods (ZnO NRs) using hydrothermal technique at different growth time. The structural and morphological properties were characterized by X-ray diffraction (XRD), Energy Dispersive X-Ray (EDX) and Field Emission Scanning Electron Microscope (FE-SEM). The ZnO NRs were obvious hexangular wurtzite structure and preferentially oriented along the c-axis (002) and growth vertically to the substrates. The optical properties were studied. From UV-Visible spectrophotometer and Photoluminescence (PL), the optical band gap energy of all ZnO NRs samples (S1, S2 and S3) were calculated to be (3.425 eV, 3.4 eV, 3.425 eV) respectively. Also, the effect of growth time on ZnO nanorods was studied.

scholarly journals Multiple-Deposition of Cadmium Oxide Nnanocrystalline Thin Films Prepared by Chemical Bath Deposition Technique

2018 ◽  
Vol 26 (10) ◽  
pp. 320-328
Author(s):  
Khalid Hamdi Rzeaj ◽  
Hani Hadi Ahmed ◽  
Jumaa Ayob Homady
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Chemical Bath Deposition ◽  
Cadmium Oxide ◽  
Morphological Properties ◽  
Deposition Technique ◽  
X Ray Diffraction ◽  
X Ray ◽  
Chemical Bath Deposition Technique ◽  
Optical Reflection

In this work CdO nanocrystalline thin films have been prepared by chemical bath deposition technique(CBD) , on commercial glass substrates at room temperature. cadmium nitrat as a source of cadmium ions(Cd+2) and Ammonium hydroxide as a source of hydroxide ions (OH-2). The effect multiple dip process on the structural and optical properties of CdO films and the use x-ray diffraction(XRD),optical reflection microscope( ORM),and UV-visible spectroscopy respectively(UV) were studied. The results of X-ray diffraction showed  that  conversion of cadmium hydroxide film to cadmium oxide film, the  results  show  of  film  and  increases grain size by increases  the multiple dip process. The optical reflection microscope showed that the films prepared has surface Morphological properties of the thin films and is improved with increased the multiple dip process. The results of optical properties showed that transmittance of film was 74% and decreased with increasing the multiple dip process, and found that the energy gap ranged from 2.24-2.63 eV. and found improved properties films with the multiple dip, This makes them suitable in solar cell applications and the detectors.

scholarly journals Doping Effect of Lead(II) on Structural and Optical Properties of Chromium Oxide Nanoparticles

2020 ◽  
Vol 32 (12) ◽  
pp. 3002-3006
Author(s):  
N. Kalaiselvi ◽  
K.U. Madhu
Keyword(s):  
Optical Properties ◽  
Chromium Oxide ◽  
Morphological Properties ◽  
Oxide Nanoparticles ◽  
X Ray Diffraction ◽  
Structural And Optical Properties ◽  
X Ray ◽  
Prepared Nanoparticles ◽  
Chromium Oxide Nanoparticles ◽  
Pure Chromium

In this work, the effects of doping post transition metal (Pb2+) on the structural, morphological, elemental and optical properties of pure chromium oxide nanoparticles are reported. The structural and morphological properties were examined by X-ray diffraction and scanning electron microscopy (SEM). The elemental composition of the prepared nanoparticles were estimated from energy dispersive X-ray (EDX) absorption spectra. The band gap energies of the prepared nanoparticles (4.72-3.78 eV) obtained from UV-vis absorption spectroscopy is higher than that of bulk Cr2O3 (3.3 eV), which ensures that the prepared nanoparticles were successfully synthesized in the nano-region.

scholarly journals γ-Rays Irradiation Induced Structural and Morphological Changes in Copper Nanowires

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
H. Shehla ◽  
F. T. Thema ◽  
A. Ishaq ◽  
Naveed Zafar Ali ◽  
I. Javed ◽  
...  
Keyword(s):  
Thin Film ◽  
Morphological Changes ◽  
High Energy ◽  
Morphological Properties ◽  
Copper Nanowires ◽  
X Ray Diffraction ◽  
Covalent Bonds ◽  
X Ray ◽  
Γ Rays ◽  
Cu Thin Film

This contribution reports on the effect ofγ-irradiations on the structural and morphological properties of copper nanowires (Cu-NWs) within theγdoses varying from 6 to 25 kGy. At 9 kGy, the Cu-NWs started welding, forming perfect X-, V-, II-, and Y-shaped molecular junctions. Further increasing theγdose up to 15 kGy caused the Cu-NWs to fuse and form larger diameter NWs. At the highest dose of 25 kGy, the nanowires converted into a continuous Cu thin film. However, X-ray diffraction (XRD) results showed that the structure of the Cu-NWs remained stable even after converting into a thin film. The formation of the Cuprite (Cu2O) phases was observed at higherγdose. The mechanism of forming welded networks of Cu-NWs and Cu thin films is explained via the short and high energyγ-ray wavelengths which act on Cu-Cu molecular covalent bonds isotropically.

scholarly journals Bismuth(III) Iodide Complexes with 1-Ethyl-4-Dimethylaminopyridinium: Structure, Thermal Stability, and Optical Properties

2021 ◽  
Vol 66 (10) ◽  
pp. 1482-1487
Author(s):  
A. N. Usol’tsev ◽  
I. A. Shentseva ◽  
V. R. Shayapov ◽  
P. E. Plyusnin ◽  
I. V. Korol’kov ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Optical Properties ◽  
Organic Solvents ◽  
X Ray Diffraction ◽  
X Ray ◽  
Thermal Stability Of

Abstract Polynuclear bismuth(III) iodide complexes with 1-ethyl-4-dimethylaminopyridinium (1-EtDMAP)4[Bi8I28] (1) and (1-EtDMAP)BiI4 (2) have been obtained by the reactions of bismuth(III) iodide with an organic iodide salt cations in organic solvents and characterized by X-ray diffraction. The optical properties and thermal stability of the obtained compounds have been studied.

Structural and optical properties of Tin Oxide and Indium doped SnO2 thin films deposited by thermal evaporation technique

2016 ◽  
Vol 12 (3) ◽  
pp. 4394-4399
Author(s):  
Sura Ali Noaman ◽  
Rashid Owaid Kadhim ◽  
Saleem Azara Hussain
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Tin Oxide ◽  
Thermal Evaporation ◽  
Pure Sno2 ◽  
X Ray Diffraction ◽  
Structural And Optical Properties ◽  
X Ray ◽  
Evaporation Technique ◽  
Sno2 Thin Films

Tin Oxide and Indium doped Tin Oxide (SnO2:In) thin films were deposited on glass and Silicon  substrates  by  thermal evaporation technique.  X-ray diffraction pattern of  pure SnO2 and SnO2:In thin films annealed at 650oC and the results showed  that the structure have tetragonal phase with preferred orientation in (110) plane. AFM studies showed an inhibition of grain growth with increase in indium concentration. SEM studies of pure  SnO2 and  Indium doped tin oxide (SnO2:In) ) thin films showed that the films with regular distribution of particles and they have spherical shape.  Optical properties such as  Transmission , optical band-gap have been measured and calculated.

Effect of Zn Content on Structure, Roughness and Corrosion Behavior of Zn-Ni Alloys

2019 ◽  
Vol 17 (17) ◽  
pp. 17-22
Author(s):  
Hayette Faid
Keyword(s):  
Corrosion Behavior ◽  
Electrochemical Impedance ◽  
Stripping Voltammetry ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ni Alloys ◽  
Sulfate Bath ◽  
Zn Content ◽  
Polarization Test ◽  
Δ Phase

AbstractIn this work, Zn-Ni alloys have been deposited on steel from sulfate bath, by electrodeposition method. The effect of Zn content on deposits properties was studied by cyclic voltammetry (CV), chronoaperometry (CA), linear stripping voltammetry (ALSV) and diffraction (XRD) and scanning electronic microscopy (SEM). The corrosion behavior in 3.5 wt. NaCl solution was examined using anodic polarization test and electrochemical impedance spectroscopy. X-ray diffraction of show that Zn-Ni alloys structure is composed of δ phase and γ phase, which increase with the decrease of Zn content in deposits. Results show that deposits obtained from bath less Zn2+ concentration exhibited better corrosion resistance.

scholarly journals Study on the Electrical, Structural, Chemical and Optical Properties of PVD Ta(N) Films Deposited with Different N2 Flow Rates

Coatings ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 937
Author(s):  
Yingying Hu ◽  
Md Rasadujjaman ◽  
Yanrong Wang ◽  
Jing Zhang ◽  
Jiang Yan ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Optical Properties ◽  
Photoelectron Spectroscopy ◽  
Crystal Size ◽  
Silicon Substrates ◽  
X Ray Diffraction ◽  
Dc Magnetron Sputtering ◽  
Flow Rates ◽  
X Ray ◽  
N2 Flow Rate

By reactive DC magnetron sputtering from a pure Ta target onto silicon substrates, Ta(N) films were prepared with different N2 flow rates of 0, 12, 17, 25, 38, and 58 sccm. The effects of N2 flow rate on the electrical properties, crystal structure, elemental composition, and optical properties of Ta(N) were studied. These properties were characterized by the four-probe method, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and spectroscopic ellipsometry (SE). Results show that the deposition rate decreases with an increase of N2 flows. Furthermore, as resistivity increases, the crystal size decreases, the crystal structure transitions from β-Ta to TaN(111), and finally becomes the N-rich phase Ta3N5(130, 040). Studying the optical properties, it is found that there are differences in the refractive index (n) and extinction coefficient (k) of Ta(N) with different thicknesses and different N2 flow rates, depending on the crystal size and crystal phase structure.

Physico-Chemical and Morphological Changes of Sayong Kaolinite Clay Treated with Sulphuric Acid for Enzyme Immobilization

2013 ◽  
Vol 832 ◽  
pp. 589-595 ◽  
Author(s):  
N.A. Edama ◽  
A. Sulaiman ◽  
K.H. Ku Hamid ◽  
M.N. Muhd Rodhi ◽  
Mohibah Musa ◽  
...  
Keyword(s):  
Surface Area ◽  
Sulphuric Acid ◽  
Enzyme Immobilization ◽  
Morphological Changes ◽  
Chemical Properties ◽  
X Ray Diffraction ◽  
Kaolinite Clay ◽  
X Ray ◽  
Mineral Oxides ◽  
Physico Chemical

This study analyzed the effects of sulphuric acid (H2SO4) treatment on pysico-chemical properties and morphological changes of clay obtained from Sg. Sayong, Perak. The clay was ground and sieved to <150μm and treated with different concentrations of H2SO4. The treatment was completed by refluxing the clay with different concentration of H2SO4 (1M, 5M and 10M ) at 100 °C for 4 hours and followed by calcination at 500 °C for 1 hour. The physic-chemical properties and morphological changes of the untreated and treated clay were compared using Surface Area Analyser, X-Ray Diffraction (XRD), Field Emission Scanning Electron Micrograph (FESEM), X-Ray Diffraction (XRD) and Fourier Transformed Infrared Spectroscopy (FTIR). The results showed that acid treatment of 5M increased the surface area from 25 m2/g to 75 m2/g and the pore volume increased from 0.1518 cc/g to 0.3546 cc/g. The nanopore size of the clay decreased from 24.8 nm to 19.4 nm after treated with acid. This can be explained due to the elimination of the exchangeable cations and generation of microporosity. The results of XRF showed SiO2 increased from 58.34% to 74.52% and Al2O3 reduced from 34.6% to 18.31%. The mineral oxides such as Fe2O3, MgO, CaO, K2O and TiO2 also reduced. This concluded that H2SO4 treatment has led to significant removal of octahedral Al3+, Fe3+ cations and other impurities. In conclusion, this study showed the physico-chemical properties and morphology of Sayong clay were improved once treated with H2SO4 and therefore suggests better supporting material for enzyme immobilization.

Sign in / Sign up

Export Citation Format

Share Document