scholarly journals Electrocatalytic properties of hydroxyapatite thin films electrodeposited on stainless steel substrates

2017 ◽  
Vol 6 (6) ◽  
pp. 255-266 ◽  
Author(s):  
Ahmed Chennah ◽  
Yassine Naciri ◽  
Hassan Ait Ahsaine ◽  
Aziz Taoufyq ◽  
Bahcine Bakiz ◽  
...  
Keyword(s):  
Thin Films ◽  
Stainless Steel ◽  
High Performance ◽  
Degradation Kinetics ◽  
Electrolytic Solution ◽  
Experimental Conditions ◽  
Energy Dispersion Spectroscopy ◽  
X Ray ◽  
Electrocatalytic Properties ◽  
Ss Substrates

In this work, we have investigated the structural, microstructural, and electrocatalytic properties of hydroxyapatite (HAp) thin films. The HAp films were electrodeposited on stainless-steel (SS) substrates by chronopotentiometry mode from an electrolytic solution. The HAp films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray energy dispersion spectroscopy (EDS). The electrodeposition and electrochemical processes of the hydroxyapatite (HAp) phase were studied by cyclic voltammetry. This HAp/SS system acting as an anode was used for the first time to electrodegrade Rhodamine B (RhB) in aqueous solutions. To follow the degradation kinetics, we used UV-visible spectroscopy. Several parameters such as the current density and the initial concentration of electrolytic solution were determined to optimize the electrodegradation of RhB. The decrease of RhB concentration followed pseudo-first order kinetics law. The rate of RhB degradation in presence of HAp/SS electrode can reach interesting high performance, depending on the electrocatalysis experimental conditions.

Use of anti-solvent to enhance thermoelectric response of hybrid-halide perovskite thin films

2022 ◽  
Author(s):  
Shrikant SAINI ◽  
Izuki Matsumoto ◽  
Sakura Kishishita ◽  
Ajay Kumar Baranwal ◽  
Tomohide Yabuki ◽  
...  
Keyword(s):  
Thin Films ◽  
Electrical Conductivity ◽  
Photoelectron Spectroscopy ◽  
High Performance ◽  
Cost Effective ◽  
Performance Tuning ◽  
Charge Carrier Density ◽  
X Ray ◽  
Thermoelectric Energy Harvesting ◽  
Halide Perovskite

Abstract Hybrid halide perovskite has been recently focused on thermoelectric energy harvesting due to the cost-effective fabrication approach and ultra-low thermal conductivity. To achieve high performance, tuning of electrical conductivity is a key parameter that is influenced by grain boundary scattering and charge carrier density. The fabrication process allows tuning these parameters. We report the use of anti-solvent to enhance the thermoelectric performance of lead-free hybrid halide perovskite, CH3NH3SnI3, thin films. Thin films with anti-solvent show higher connectivity in grains and higher Sn+4 oxidation states which results in enhancing the value of electrical conductivity. Thin films were prepared by a cost-effective wet process. Structural and chemical characterizations were performed using x-ray diffraction, scanning electron microscope, and x-ray photoelectron spectroscopy. The value of electrical conductivity and the Seebeck coefficient were measured near room temperature. The high value of power factor (1.55 µW/m.K2 at 320 K) was achieved for thin films treated with anti-solvent.

scholarly journals X-ray Diffraction Investigation of Stainless Steel—Nitrogen Thin Films Deposited Using Reactive Sputter Deposition

Coatings ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 984
Author(s):  
Faisal I. Alresheedi ◽  
James E. Krzanowski
Keyword(s):  
Thin Films ◽  
Stainless Steel ◽  
Substrate Temperature ◽  
Peak Shift ◽  
304 Stainless Steel ◽  
Tetragonal Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Area Detector ◽  
Calculated Parameter

An X-ray diffraction investigation was carried out on nitrogen-containing 304 stainless steel thin films deposited by reactive rf magnetron sputtering over a range of substrate temperature and bias levels. The resulting films contained between ~28 and 32 at.% nitrogen. X-ray analysis was carried out using both the standard Bragg-Brentano method as well as area-detector diffractometry analysis. The extent of the diffraction anomaly ((002) peak shift) was determined using a calculated parameter, denoted RB, which is based on the (111) and (002) peak positions. The normal value for RB for FCC-based structures is 0.75 but increases as the (002) peak is anomalously displaced closer to the (111) peak. In this study, the RB values for the deposited films were found to increase with substrate bias but decrease with substrate temperature (but still always >0.75). Using area detector diffractometry, we were able to measure d111/d002 values for similarly oriented grains within the films, and using these values calculate c/a ratios based on a tetragonal-structure model. These results allowed prediction of the (002)/(200) peak split for tetragonal structures. Despite predicting a reasonably accessible split (~0.6°–2.9°–2θ), no peak splitting observed, negating the tetragonal-structure hypothesis. Based on the effects of film bias/temperature on RB values, a defect-based hypothesis is more viable as an explanation for the diffraction anomaly.

scholarly journals Silica-Copper Oxide Composite Thin Films as Solar Selective Coatings Prepared by Dipping Sol Gel

2008 ◽  
Vol 2008 ◽  
pp. 1-5 ◽  
Author(s):  
E. Barrera-Calva ◽  
J. Méndez-Vivar ◽  
M. Ortega-López ◽  
L. Huerta-Arcos ◽  
J. Morales-Corona ◽  
...  
Keyword(s):  
Thin Films ◽  
Stainless Steel ◽  
Copper Oxide ◽  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Silica Matrix ◽  
Composite Thin Films ◽  
X Ray ◽  
Molar Ratios ◽  
Steel Substrates

Silica-copper oxide (silica-CuO) composite thin films were prepared by a dipping sol-gel route using ethanolic solutions comprised TEOS and a copper-propionate complex. Sols with different TEOS/Cu-propionate (Si/Cu) molar ratios were prepared and applied on stainless steel substrates using dipping process. During the annealing process, copper-propionate complexes developed into particulate polycrystalline CuO dispersed in a partially crystallized silica matrix, as indicated by the X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses. The gel thermal analysis revealed that the prepared material might be stable up to400°C. The silica-CuO/stainless steel system was characterized as a selective absorber surface and its solar selectivity parameters, absorptance (α), and emittance (ε) were evaluated from UV-NIR reflectance data. The solar parameters of such a system were mostly affected by the thickness and phase composition of theSiO2-CuO film. Interestingly, the best solar parameters (α= 0.92 andε= 0.2) were associated to the thinnest films, which comprised a CuO-Cu2Omixture immersed in the silica matrix, as indicated by XPS.

PHOTOCATALYTIC DEGRADATION OF PYRENE IN POROUS Pt/TiO2–SiO2 PHOTOCATALYST SUSPENSION UNDER UV IRRADIATION

NANO ◽  
2008 ◽  
Vol 03 (05) ◽  
pp. 317-322 ◽  
Author(s):  
ZHAOHUI LUO ◽  
KEIKO KATAYAMA-HIRAYAMA ◽  
KIMIAKI HIRAYAMA ◽  
TETSUYA AKITSU ◽  
HIDEHIRO KANEKO
Keyword(s):  
Molecular Weight ◽  
Photocatalytic Degradation ◽  
High Molecular Weight ◽  
Uv Irradiation ◽  
Degradation Kinetics ◽  
Degradation Process ◽  
Bet Surface Area ◽  
Experimental Conditions ◽  
Initial Concentration ◽  
X Ray

Pyrene is a high molecular weight polycyclic aromatic hydrocarbon (PAH) that is found in water systems worldwide. It is harmful to living organisms, even when taken in very small amounts. The photocatalytic degradation of pyrene in porous Pt / TiO 2– SiO 2 photocatalyst (PPtPC) suspension under UV irradiation was investigated in this study. PPtPC was prepared by a simple heat treatment of the compacted powder mixtures of anatase TiO 2 and amorphous SiO 2 with camphor as a pore directing template, followed by coating platinum by the dip-coating method. X-ray diffraction (XRD), scanning electron microscopy (SEM) with an integrated energy-dispersive analysis of the X-ray (EDX) system, and Brunauer–Emmett–Teller (BET) were used to characterize PPtPC. The degradation kinetics of pyrene in different experimental conditions, such as initial concentration of pyrene, oxygen concentrations, pH, and temperature, were investigated. The durability of PPtPC was also tested. The results indicate that the structure of TiO 2 in PPtPC is anatase. The aggregated size of PPtPC is in the range of 10–100 μm, the mean pore diameter is 3 nm, and the BET surface area is 109 m2 g-1. The photocatalytic degradation process of pyrene follows pseudo-first-order kinetics. The rate constants increase as the initial concentration of pyrene and pH decrease. Higher temperature slightly enhances the rate constant. The dissolved oxygen in the photocatalytic degradation process is not as important as in the photolysis process. The recovered PPtPC still shows high photoactivity. This work suggests that PPtPC offers a promising method for high molecular weight PAH removal.

Lead Titanate Thin Films Prepared by Metallorganic Chemical Vapor Deposion (MOCVD) on Sapphire, Pt, and RuOx Substrates

1993 ◽  
Vol 335 ◽  
Author(s):  
Warren C. Hendricks ◽  
Seshu B. Desu ◽  
Chien H. Peng
Keyword(s):  
Thin Films ◽  
Ruthenium Oxide ◽  
Chemical Vapor ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
X Ray ◽  
Composition Control ◽  
Oxide Substrates ◽  
Temperature Deposition ◽  
Titanium Ethoxide

AbstractTransparent and highly specular PbTiO3 thin films were deposited on sapphire, platinum and ruthenium oxide-coated silicon wafers by hot-wall metallorganic chemical vapor deposition (MOCVD). Lead bis-tetramethylheptadionate and titanium ethoxide were used as chemical precursors. Films were deposited over a range of experimental conditions. X-ray diffraction (XRD) was used to determine the phases present in the films; Scanning Electron Microscopy (SEM) was used to examine the surface morphology and Energy Dispersive Spectroscopy (EDS) was used to determine the composition. Optical spectra were obtained to confirm the highly dense and transparent nature of the films. The chemical stability of the ruthenium oxide substrates in the MOCVD environment as well as the existence of a high-temperature deposition regime for composition control are also discussed.

scholarly journals Electro-Precipitation of Actinides on Boron-Doped Diamond Thin Films for Solid Sources Preparation for High-Resolution Alpha-Particle Spectrometry

2019 ◽  
Vol 9 (7) ◽  
pp. 1473 ◽  
Author(s):  
Quang-Thuan Tran ◽  
Sylvie Pierre ◽  
Jacques de Sanoit ◽  
Michal Pomorski ◽  
Philippe Bergonzo
Keyword(s):  
Stainless Steel ◽  
High Resolution ◽  
Alpha Particle ◽  
High Performance ◽  
High Resolution Spectroscopy ◽  
Precipitation Process ◽  
Boron Doped Diamond ◽  
Experimental Conditions ◽  
Boron Doped ◽  
Novel Approach

In this work, we investigate a novel approach to prepare high-performance alpha-particle solid sources fabricated on diamond thin support layers, offering the properties of diamond such as a low-Z material with corrosion and mechanical hardness. As-prepared solid sources onto boron-doped-diamond (BDD) substrate exhibited high performance of the autoradiography and spectroscopic resolution at the level of other more conventional materials such as stainless steel. A straightforward precipitation process in the Na2SO4 or NaNO3 simple electrolytes under mild experimental conditions with a low current of several mA.cm−2 were successfully developed onto BDD substrates for deposition of single 241Am as well as 239Pu, 241Am, and 244Cm mixed radionuclides. The results demonstrate that solid sources deposited onto such BDD substrates can match the performance of those prepared onto stainless steel substrates with excellent uniformity and high-resolution spectroscopy, together combining the robustness, chemical resilience, and X-ray transparence of the diamond. Alpha-particle spectra exhibiting a low full width at half maximum (FWHM) of 12.5 keV at the energy of 5.485 MeV (241Am) could be practically obtained for BDD substrates.

PREFERABLE ORIENTATION OF CRYSTALLINE THIN-FILM OF MODIFIED BNN SYSTEM

1989 ◽  
Vol 03 (06) ◽  
pp. 465-470 ◽  
Author(s):  
MASAYUKI TSUKIOKA ◽  
TASUKU MASHIO ◽  
MASAJI SHIMAZU ◽  
TAKESHI NAKAMURA
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Stainless Steel ◽  
Steel Substrate ◽  
Rf Sputtering ◽  
Polished Surface ◽  
Diffraction Measurement ◽  
X Ray Diffraction ◽  
X Ray ◽  
Quantitative Analyses

Using rf-sputtering method, modified BNN ( Ba 2 NaNb 5 O 15) thin-films, which are highly aligned, were prepared on a polished surface of a stainless steel plate and on a polished silicon wafer. It was found that preferably aligned thin-films were successfully obtained only when modified Nb-rich BNN target was used. Preferable orientation of these thin-films was confirmed by X-ray diffraction measurement. In order to find the correlation between preferable orientation and separation from plasma center, X-ray measurement was carried out at several points on the thin-film sputtered on a long stainless steel substrate (5×100 mm ). The result indicated that preferable orientation was dominant near the position of plasma center. In order to distinguish whether the strong X-ray peak observed in the preferably aligned BNN thin-film is due to (200) peak of Nb 2 O 5 or (440) peak of BNN, X-ray measurements and the following quantitative analyses; fluorescent X-ray, ICP (Induced Coupled Radio Frequency Plasma) and an Atomic Absorption Method, were carried out for films sputtered from Nb-rich BNN target. The results reveal that the thin-films include considerable quantity of barium and sodium. This suggests that the highly aligned thin-film is composed of modified BNN and not Nb 2 O 5.

Investigation of crystal growth on (111) InSb thin films to produce high performance Hall elements

1999 ◽  
Vol 14 (1) ◽  
pp. 39-43 ◽  
Author(s):  
Toshiaki Fukunaka ◽  
Takek Matsui ◽  
Shin-ya Matsuno
Keyword(s):  
Thin Films ◽  
Crystal Growth ◽  
High Performance ◽  
Flux Ratio ◽  
High Electron ◽  
High Electron Mobility ◽  
X Ray ◽  
Insb Thin Films ◽  
Electromagnetic Characteristics ◽  
Hall Elements

The crystal growth of InSb thin films on mica substrates was investigated by conventional three temperature vacuum evaporation with varied Sb/In flux ratios and temperature programming for the substrate. The Sb/In flux ratio was varied from higher than 1.0 (about 2.0 is optimum), to less than 1.0 (about 0.7 is optimum), to again much higher than 1.0 during the stages of evaporation. The electromagnetic characteristics were investigated and x-ray analysis of the films at various stages was undertaken. The films obtained contained no excess In and they were (111) highly oriented in x-ray analysis, showing high electron mobility. These films were used to prepare high performance Hall elements.

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