Solar Selective Properties of Electrolytically Formed Thin Layers on Aluminum

A novel electrochemical process for the formation of solar selective absorber layers on aluminum is presented. The growth of an alumina layer and the incorporation of metal ions into the layer is done by a one-step procedure using only one electrolytic bath and application of a voltage pulse technique. The influence of selected electrical parameters on the solar selective properties is described and the enhanced stability of an absorber layer, attained by a sol-gel-posttreatment, is discussed. [S0199-6231(00)00602-X]

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Microwave-Assisted Vacuum Synthesis of TiO2 Nanocrystalline Powders in One-Pot, One-Step Procedure

Nanomaterials ◽

10.3390/nano12010149 ◽

2021 ◽

Vol 12 (1) ◽

pp. 149

Author(s):

Enrico Paradisi ◽

Roberto Rosa ◽

Giovanni Baldi ◽

Valentina Dami ◽

Andrea Cioni ◽

...

Keyword(s):

Photocatalytic Activity ◽

Sol Gel ◽

Reaction Medium ◽

Process Intensification ◽

Nanocrystalline Powders ◽

Fast Heating ◽

One Pot ◽

Nanoparticle Suspension ◽

Step Procedure ◽

One Step

A new method for fast and simple synthesis of crystalline TiO2 nanoparticles with photocatalytic activity was developed by carrying out a classic sol–gel reaction directly under vacuum. The use of microwaves for fast heating of the reaction medium further reduces synthesis times. When the solvent is completely removed by vacuum, the product is obtained in the form of a powder that can be easily redispersed in water to yield a stable nanoparticle suspension, exhibiting a comparable photocatalytic activity with respect to a commercial product. The present methodology can, therefore, be considered a process intensification procedure for the production of nanotitania.

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Ceramic Nanomaterials Based on the Barium and Titanium Compounds, Prepared by the Sol - Gel Method, for Elecrotechnical Applications

Archives of Metallurgy and Materials ◽

10.2478/v10172-011-0117-6 ◽

2011 ◽

Vol 56 (4) ◽

pp. 1057-1064

Author(s):

K. Kogut ◽

B. Zboromirska-Wnukiewicz ◽

K. Kasprzyk

Keyword(s):

Sol Gel ◽

Low Frequency ◽

Microscopic Analysis ◽

Thin Layers ◽

Electrical Parameters ◽

Gel Method ◽

Sol Gel Method ◽

Electrical Capacity ◽

Electrical Permittivity ◽

Titanium Compounds

Ceramic Nanomaterials Based on the Barium and Titanium Compounds, Prepared by the Sol - Gel Method, for Elecrotechnical Applications This paper describes the sol - gel method barium and titanium compounds materials obtaining, which their physicochemical parameters could be competitive with the materials obtained by classic methods. Additionally dielectric thin layers was obtained with the use of spin and dip coaters. Based on selected precursor elements which form appropriate crystal net, the capacitance construction was created. Dielectric in this contraction was a barium titanate with high electrical permittivity and small grain size. The optimal dry, calcinations and sintering temperature of the dielectric with base was determined. On that capacitor the microscopic analysis with the use of scanning electron microscope (SEM) was carried out. The thickness of the dielectric layer and electrical parameters use by impedance analyzer Solatron SI 1260 was carried out. The capacitance, dielectric loss and electrical permittivity was carried out, cooperative influence of the frequency and temperature on the measurements was determined. The best results had a samples sintered in the 1000°C. The electrical permittivity for measurements in few Hertz for the samples with the base of nickel and BaTiO3 layer coated by spin and dip coaters, in the room temperature and measurements for few Hertz, amount to 4700. The electrical capacity for low frequency was about 3,2·10-8F.

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One-step conversion of CsPbBr3 into Cs4PbBr6/CsPbBr3@Ta2O5 core–shell microcrystals with enhanced stability and photoluminescence

Journal of Materials Chemistry C ◽

10.1039/d0tc05039c ◽

2021 ◽

Author(s):

Manli Zhang ◽

Yao Li ◽

Kaimin Du ◽

Xuan Gao ◽

Yu Lu ◽

...

Keyword(s):

Room Temperature ◽

Sol Gel ◽

Core Shell ◽

Photoluminescence Properties ◽

Gel Method ◽

Sol Gel Method ◽

One Step ◽

Enhanced Stability

Cs4PbBr6/CsPbBr3@Ta2O5 microcrystals were prepared through a one-step sol–gel method at room temperature. It possesses better stability and photoluminescence properties than Cs4PbBr6/CsPbBr3.

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Tuned S-Scheme Cu2S_TiO2_WO3 Heterostructure Photocatalyst toward S-Metolachlor (S-MCh) Herbicide Removal

Materials ◽

10.3390/ma14092231 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2231

Author(s):

Alexandru Enesca ◽

Luminita Isac

Keyword(s):

Sol Gel ◽

Annealing Treatment ◽

Atomic Ratio ◽

High Concentration ◽

Step Procedure ◽

Constant Rate ◽

Efficient Charge ◽

Crystallite Sizes ◽

Oxygen Excess ◽

And Migration

A dual S-scheme Cu2S_TiO2_WO3 heterostructure was constructed by sol–gel method using a two-step procedure. Due to the synthesis parameters and annealing treatment the heterostructure is characterized by sulfur deficit and oxygen excess allowing the passivation of oxygen vacancies. The photocatalytic activity was evaluated under UV and UV–Vis irradiation scenarios using S-MCh as reference pollutant. The heterostructure is composed on orthorhombic Cu2S, anatase TiO2 and monoclinic WO3 with crystallite sizes varying from 65.2 Å for Cu2S to 97.1 Å for WO3. The heterostructure exhibit a dense morphology with pellets and particle-like morphology closely combined in a relatively compact assembly. The surface elemental composition indicate that the heterostructure maintain a similar atomic ratio as established during the synthesis with a slight sulfur deficit due to the annealing treatments. The results indicate that the three-component heterostructure have higher photocatalytic efficiency (61%) comparing with two-component heterostructure or bare components. Moreover, Cu2S_TiO2_WO3 exhibit a superior constant rate (0.114 s−1) due to the high concentration of photogenerated charge carriers, efficient charge separation and migration.

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Electrochromic Performance and Capacitor Performance of α-MoO3 Nanorods Fabricated by a One-Step Procedure

Coatings ◽

10.3390/coatings11070783 ◽

2021 ◽

Vol 11 (7) ◽

pp. 783

Author(s):

Ying Duan ◽

Chen Wang ◽

Jian Hao ◽

Yang Jiao ◽

Yanchao Xu ◽

...

Keyword(s):

Growth Parameters ◽

Average Diameter ◽

Fast Response ◽

Cycle Stability ◽

Electrochromic Devices ◽

Step Procedure ◽

One Step ◽

Supercapacitor Performance ◽

First Time ◽

Prepared Nanorods

In this paper, we propose for the first time the synthesis of α-MoO3 nanorods in a one-step procedure at mild temperatures. By changing the growth parameters, the microstructure and controllable morphology of the resulting products can be customized. The average diameter of the as-prepared nanorods is about 200 nm. The electrochromic and capacitance properties of the synthesized products were studied. The results show that the electrochromic properties of α-MoO3 nanorods at 550 nm have 67% high transmission contrast, good cycle stability and fast response time. The MoO3 nanorods also exhibit a stable supercapacitor performance with 98.5% capacitance retention after 10,000 cycles. Although current density varies sequentially, the nanostructure always exhibits a stable capacitor to maintain 100%. These results indicate the as-prepared MoO3 nanorods may be good candidates for applications in electrochromic devices and supercapacitors.

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Manufacturing Processes of Solid Oxide Fuel Cell Components

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.498 ◽

2007 ◽

Vol 336-338 ◽

pp. 498-501

Author(s):

Xian Feng Jiang ◽

Min Fang Han ◽

Su Ping Peng

Keyword(s):

Fuel Cell ◽

Solid Oxide Fuel Cell ◽

Screen Printing ◽

Sol Gel ◽

Tape Casting ◽

Solid Oxide ◽

Oxide Fuel ◽

Cell Components ◽

One Step ◽

Made In

The all processes for manufacturing materials parts of solid oxide fuel cell (SOFC) are discussed in the paper. The films are made in one step by the ways of APS, VPS, EVD, which are usually used to produce the electrolyte and interconnect. The films are thin and good gas-resistance, but with relatively high cost. All parts of SOFC are made by the following ways, such as sol-gel, tape casting, tape calendaring and screen printing, which are suitable for manufacturing samples in industry with the cheapest process by co-sintered together ways.

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Sodium Solid Electrolytes: NaxAlOy Bilayer-System Based on Macroporous Bulk Material and Dense Thin-Film

Materials ◽

10.3390/ma14040854 ◽

2021 ◽

Vol 14 (4) ◽

pp. 854

Author(s):

Antonia Hoppe ◽

Cornelius Dirksen ◽

Karl Skadell ◽

Michael Stelter ◽

Matthias Schulz ◽

...

Keyword(s):

Pore Size ◽

Bulk Material ◽

Sol Gel ◽

Dense Layer ◽

X Ray Diffraction ◽

Bilayer System ◽

Step Procedure ◽

Short Circuits ◽

Α Al2o3 ◽

Sol Gel Synthesis

A new preparation concept of a partially porous solid-state bilayer electrolyte (BE) for high-temperature sodium-ion batteries has been developed. The porous layer provides mechanical strength and is infiltrated with liquid and highly conductive NaAlCl4 salt, while the dense layer prevents short circuits. Both layers consist, at least partially, of Na-β-alumina. The BEs are synthesized by a three-step procedure, including a sol-gel synthesis, the preparation of porous, calcined bulk material, and spin coating to deposit a dense layer. A detailed study is carried out to investigate the effect of polyethylene oxide (PEO) concentration on pore size and crystallization of the bulk material. The microstructure and crystallographic composition are verified for all steps via mercury intrusion, X-ray diffraction, and scanning electron microscopy. The porous bulk material exhibits an unprecedented open porosity for a NaxAlOy bilayer-system of ≤57% with a pore size of ≈200–300 nm and pore volume of ≤0.3 cm3∙g−1. It contains high shares of crystalline α-Al2O3 and Na-β-alumina. The BEs are characterized by impedance spectroscopy, which proved an increase of ionic conductivity with increasing porosity and increasing Na-β-alumina phase content in the bulk material. Ion conductivity of up to 0.10 S∙cm−1 at 300 °C is achieved.

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