Synthesis of Alumina and Aluminum Nitride Layers on a Graphitic Substrate via a Sol-Gel Route

2010 ◽  
Vol 63 ◽  
pp. 24-29
Author(s):  
Florian Fontaine ◽  
René Pailler ◽  
Alain Guette
Keyword(s):  
Heat Treatment ◽  
Aluminum Nitride ◽  
Sol Gel ◽  
Nitride Layer ◽  
Carbon Substrate ◽  
Alumina Layer ◽  
Turbostratic Carbon ◽  
Treatment Conditions ◽  
Nitride Layers ◽  
The Impact

In this study, our objective is to deposit an alumina or an aluminum nitride layer on a turbostratic carbon substrate. The coatings are synthesized via a sol-gel route followed by a heat treatment in order to obtain -alumina or hexagonal aluminum nitride by carbothermal nitridation of alumina. The synthesis of such layers on carbon substrates is not reported in literature. Several slurries were elaborated using various solvents and catalysts, and aluminum-tri-sec-butoxide as an aluminum precursor. The coating is obtained by dropping the substrate in the sol. After drying and pyrolysis, the amorphous alumina layer obtained has a thickness ranging from 500 nm to 1 µm. The material is finally heat treated. Several treatment conditions were evaluated. A thermodynamic study of the Al-C-O-N system will be drawn, and the composition of the synthesized sol-gel and heat treatment parameters will be detailed. Then, the layer’s morphology and structure will be characterized thanks to Scanning Electron Microscopy and X-Ray Diffraction analyses. The impact of heat treatment parameters will be discussed and experimental results will be compared to the theoretical thermodynamic results.

LiNiO2 Thin Films Fabricated by Diffusion of Li on Ni Tapes

2007 ◽  
Vol 336-338 ◽  
pp. 505-508
Author(s):  
Cheol Jin Kim ◽  
In Sup Ahn ◽  
Kwon Koo Cho ◽  
Sung Gap Lee ◽  
Jun Ki Chung
Keyword(s):  
Thin Films ◽  
Heat Treatment ◽  
Grain Size ◽  
Sol Gel ◽  
Surface Oxidation ◽  
Cold Isostatic Pressing ◽  
Tube Furnace ◽  
Treatment Conditions ◽  
Average Grain Size ◽  
Cold Rolling And Annealing

LiNiO2 thin films for the application of cathode of the rechargeable battery were fabricated by Li ion diffusion on the surface oxidized NiO layer. Bi-axially textured Ni-tapes with 50 ~ 80 μm thickness were fabricated using cold rolling and annealing of Ni-rod prepared by cold isostatic pressing of Ni powder. Surface oxidation of Ni-tapes were conducted using tube furnace or line-focused infrared heater at 700 °C for 150 sec in flowing oxygen atmosphere, resulted in NiO layer with thickness of 400 and 800 μm, respectively. After Li was deposited on the NiO layer by thermal evaporation, LiNiO2 was formed by Li diffusion through the NiO layer during subsequent heat treatment using IR heater with various heat treatment conditions. IR-heating resulted in the smoother surface and finer grain size of NiO and LiNiO2 layer compared to the tube-furnace heating. The average grain size of LiNiO2 layer was 0.5~1 μm, which is much smaller than that of sol-gel processed LiNiO2. The reacted LiNiO2 region showed homogeneous composition throughout the thickness and did not show any noticeable defects frequently found in the solid state reacted LiNiO2, but crack and delamination between the reacted LiNiO2 and Ni occurred as the reaction time increased above 4hrs.

Characteristics of Lithium Polysilicate Electrolyte Synthesized by Sol-Gel Processing

2007 ◽  
Vol 124-126 ◽  
pp. 1031-1034
Author(s):  
Bong Soo Jin ◽  
Bok Ki Min ◽  
Chil Hoon Doh
Keyword(s):  
Heat Treatment ◽  
Acid Treatment ◽  
Treatment Time ◽  
Sol Gel ◽  
Silicate Solution ◽  
Treatment Temperature ◽  
Lithium Silicate ◽  
Treatment Conditions ◽  
Xrd Patterns ◽  
Si Wafer

To find out suitable Si surface treatment and heat treatment conditions, acid treatment of Si wafer was done for lithium polysilicate electrolyte coating on Si wafer. In case of HCl treatment, the wet angle of a sample is 30o, which is the smallest wet angle of other acid in this experiment. Acid treatment time is 10 min, which is no more change of wet angle. Lithium polysilicate electrolyte was synthesized by hydrolysis and condensation of lithium silicate solution using perchloric acid. Thermal analysis of lithium polysilicate electrolyte shows the weight loss of ~23 % between 400 and 500 , which is due to the decomposition of LiClO4. The XRD patterns of the obtained lithium polysilicate electrolyte also show the decrement of LiClO4 peak at 400 . The optimum heat treatment temperature is below 400 , which is the suitable answer for lithium polysilicate electrolyte.

The Process of Sol-Gel Method Prepared Bi-2212 Superconductors Tapes

2013 ◽  
Vol 275-277 ◽  
pp. 2300-2303
Author(s):  
Gen Zong Song ◽  
Duo Zhang
Keyword(s):  
Heat Treatment ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Ni Substrate ◽  
Treatment Conditions ◽  
Drying Conditions ◽  
And Control

In this dissertation, Bi-2212 superconducting tapes was prepared by sol-gel method, in addition we mainly studied heat treatment conditions and sintering material drying conditions of the NiO/Ni substrate, and gived a optimization to the process. The heat treatment process of the NiO/Ni substrate had been researched.Based on previous experience, we explored the temperature of heat treatment and improved the process.Afterheattreatment,the samples was analyzed by metallographic microscope and X-ray diffraction,and we analysed these data. It’s concluded that the dense uniform oxide film can be sintered in 800°C with a 3 hours’ heat treatment.We further explored the conditions of the Bi-2212 superconducting materials.During the preparation. We mainly studied the drying temperature and sintering temperature ,because they would affect the gel phase transition and control components. It has a very important effect on high-quality superconducting strip preparation. Experiments results showed that drying the sample at 510 °C in temperature is best. all the samples was analyzed by X-ray diffraction. We summed up the data derived from experiments , it showed that sintering the sample at 850°C,we can obtain the mixed phase of Bi-2201 and Bi-2212.

Effect of heat treatment conditions on the growth of MgAl2O4 nanoparticles obtained by sol-gel method

2017 ◽  
Vol 43 (17) ◽  
pp. 15246-15253 ◽  
Author(s):  
Yubin Wen ◽  
Xinhong Liu ◽  
Xiaoyu Chen ◽  
Quanli Jia ◽  
Renhong Yu ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Sol Gel ◽  
Gel Method ◽  
Sol Gel Method ◽  
Treatment Conditions

scholarly journals Effect of Heat Treatment on Structural, Magnetic and Electrical Properties of La2FeMnO6

Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7501
Author(s):  
Djoko Triyono ◽  
Y Yunida ◽  
Rifqi Almusawi Rafsanjani
Keyword(s):  
Heat Treatment ◽  
Electrical Properties ◽  
Calcination Temperature ◽  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Phonon Modes ◽  
Magnetic Exchange ◽  
X Ray ◽  
Treatment Conditions ◽  
Magnetic And Electrical Properties

In this study, the effect of heat treatment on the structural, magnetic and electrical properties of La2FeMnO6 prepared via the sol–gel and sintering method were investigated. The heat-treatment conditions, i.e., the calcination temperature (1023 K and 1173 K), sintering temperature and time (1273 K for 1 and 3 h) were carried out. X-ray diffraction (XRD) revealed orthorhombic pnma (62) symmetry without any impurity phase for all samples. X-ray photoelectron spectroscopy confirmed the presence of Fe2+–Fe3+–Fe4+ and Mn3+–Mn4+ mixed states, and lanthanum and oxygen vacancies resulting in various magnetic exchange interactions. Furthermore, the magnetisation hysteresis showed enhanced hysteresis loops accompanied by an increase in magnetisation parameters with calcination temperature. The Raman phonon parameters induced a redshift in the phonon modes, alongside an increase in the intensity and compression of the linewidth, reflecting a decrease in lattice distortion, which was confirmed by XRD. The temperature-dependent conductivity showed that the conduction mechanism is dominated by p-type polaron hopping, and the lowest activation energy was approximately 0.237 ± 0.003 eV for the minimum heat-treatment conditions. These results show that varying heat-treatment conditions can significantly affect the structural, magnetic and electrical properties of the La2FeMnO6 system.

Influence of Heat Treatment on the Structure and Performance of ATP and its Catalyzer

2011 ◽  
Vol 295-297 ◽  
pp. 1510-1515 ◽  
Author(s):  
Yue Bin Lin ◽  
Chun Bo Li ◽  
Yu Fu Zhu ◽  
Ai Hui Liu
Keyword(s):  
Heat Treatment ◽  
Thermal Analysis ◽  
Spectroscopic Analysis ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Treatment Conditions ◽  
Transmission Electron ◽  
Crystal Transition ◽  
And Performance

Taking Attapulgite Clay(ATP) as a carrier, TiO2/ATP precursor was prepared by acid sol-gel method, and then made its composite under different heat-treatment conditions. The structures, dimensions, compositions of the composite are characterized by X-Ray diffraction, transmission electron microscope, thermogravimetric-differential thermal analysis and spectroscopic analysis measurements, respectively. the results show that TiO2/ATP composite increase the crystal transition temperature of TiO2, rutile TiO2emerge in the composite until 800°C, ATP lost its layer constructure and collapse at 850°C.

Effect of Heat Treatment on Structural, Magnetic and Electric Properties of Z-Type Barium Cobalt Hexaferrite Powder

2014 ◽  
Vol 938 ◽  
pp. 24-29 ◽  
Author(s):  
Neha Solanki ◽  
G. Packiaraj ◽  
Rajshree B. Jotania
Keyword(s):  
Heat Treatment ◽  
Ac Conductivity ◽  
Room Temperature ◽  
Sintering Temperature ◽  
Sol Gel ◽  
Frequency Range ◽  
Treatment Conditions ◽  
Auto Combustion ◽  
Powder Samples ◽  
Combustion Technique

Z-type hexaferrite with composition Ba3Co2Fe24O41has been synthesized using a sol-gel auto combustion technique. The obtain combusted powder was sintered at 500 OC and followed by 950 OC for 4 hrs in a muffle furnace. The effect of different sintering temperature on crystal structure, crystallite size, microstructure and dielectric properties were systematically investigated. The prepared barium cobalt hexaferrite powder samples were characterized using different experimental techniques like FTIR, XRD, AC conductivity and specific magnetization measurements. It was observed from XRD results that heat treatment conditions play significant role in the formation of hexaferrite phase. AC conductivity measurements were carried out at room temperature in frequency range of 20Hz to 2MHz. All the samples show the frequency dependent phenomena, i.e. the AC conductivity increases with increasing frequency.

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