scholarly journals Photocatalytical Properties and Theoretical Analysis of N, Cd-Codoped TiO2Synthesized by Thermal Decomposition Method

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Hongtao Gao ◽  
Bing Lu ◽  
Fangfang Liu ◽  
Yuanyuan Liu ◽  
Xian Zhao
Keyword(s):  
Thermal Decomposition ◽  
Theoretical Analysis ◽  
Valence Band ◽  
Conduction Band ◽  
Photoelectron Spectroscopy ◽  
Decomposition Method ◽  
Density Functional ◽  
X Ray ◽  
Thermal Decomposition Method ◽  
Bet Specific Surface Area

N, Cd-codoped TiO2have been synthesized by thermal decomposition method. The products were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), UV-visible diffuse reflectance spectra (DRS), X-ray photoelectron spectroscopy (XPS), and Brunauer-Emmett-Teller (BET) specific surface area analysis, respectively. The products represented good performance in photocatalytic degradation of methyl orange. The effect of the incorporation of N and Cd on electronic structure and optical properties of TiO2was studied by first-principle calculations on the basis of density functional theory (DFT). The impurity states, introduced by N 2p or Cd 5d, lied between the valence band and the conduction band. Due to dopants, the band gap of N, Cd-codoped TiO2became narrow. The electronic transition from the valence band to conduction band became easy, which could account for the observed photocatalytic performance of N, Cd-codoped TiO2. The theoretical analysis might provide a probable reference for the experimentally element-doped TiO2synthesis.

Experimental and First-Principles Studies of the Band Alignment at the HfO2/4H-SiC (0001) Interface

2006 ◽  
Vol 527-529 ◽  
pp. 1071-1074 ◽  
Author(s):  
Carey M. Tanner ◽  
Jong Woo Choi ◽  
Jane P. Chang
Keyword(s):  
Conduction Band ◽  
Photoelectron Spectroscopy ◽  
Density Functional ◽  
Atomic Layer ◽  
Band Alignment ◽  
Functional Theory ◽  
X Ray ◽  
Conduction Band Offset ◽  
Mos Devices ◽  
Layer Deposition

The electronic properties of HfO2 films on 4H-SiC were investigated to determine their suitability as high-κ dielectrics in SiC power MOS devices. The band alignment at the HfO2/4HSiC interface was determined by X-ray photoelectron spectroscopy (XPS) and supported by density functional theory (DFT) calculations. For the experimental study, HfO2 films were deposited on ntype 4H-SiC by atomic layer deposition (ALD). XPS analysis yielded valence and conduction band offsets of 1.69 eV and 0.75 eV, respectively. DFT predictions based on two monoclinic HfO2/4HSiC (0001) structures agree well with this result. The small conduction band offset suggests the potential need for further interface engineering and/or a buffer layer to minimize electron injection into the gate oxide.

Physicochemical Properties of Hydroxyapatite Extracted from Fish Scales

2012 ◽  
Vol 545 ◽  
pp. 235-239 ◽  
Author(s):  
Ismail Zainon ◽  
N.M. Alwi ◽  
M.Z. Abidin ◽  
H.M.Z. Haniza ◽  
M.S. Ahmad ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Freshwater Fish ◽  
Decomposition Method ◽  
Heating Temperature ◽  
Fish Scales ◽  
X Ray ◽  
Thermal Decomposition Method ◽  
Saltwater Fish ◽  
The World ◽  
Raw Fish

In this study, hydroxyapatite (HAp) was extracted from freshwater fish scales and saltwater fish scales using thermal decomposition method at various temperatures. The percentages of HAp in each species of raw fish scales were analysed using thermogravimetry analysis (TGA) whereas Fourier transform infrared (FTIR) was used to confirm the present of HA. The crystallinity of the HAp was studied using x-ray diffractometer (XRD). TGA and FTIR are found to be useful techniques to predict the composition of the HAp present in the fish scales. The results show that the composition of HAp in the fish scales was not significantly dependent on the species of the fish. The percentage of HAp in the fish scales ranged from 40 to 45 wt%. The heating temperature had an effect on the crystallinity and colour of the HAp produced. Results from FTIR and XRD confirmed that the HAp extracted from fish scales was similar to the HAp standard. However, the natural HAp produced from saltwater fish scales was more crystalline than that produced from freshwater fish scales. The HAp produced from this study is relatively cheap and more importantly they are HALAL for four billion Muslims population around the world.

scholarly journals Extraction of Hydroxyapatite from Fish Scales and Its Integration with Rice Husk for Ammonia Removal in Aquaculture Wastewater

2019 ◽  
Vol 19 (4) ◽  
pp. 1019
Author(s):  
Sofiah Hamzah ◽  
Norhafiza Ilyana Yatim ◽  
Maslinda Alias ◽  
Asmadi Ali
Keyword(s):  
Thermal Decomposition ◽  
Rice Husk ◽  
Decomposition Method ◽  
Ammonia Removal ◽  
Fish Scales ◽  
X Ray Diffraction ◽  
Coating Agent ◽  
X Ray ◽  
Thermal Decomposition Method ◽  
Aquaculture Wastewater

Aquaculture plays an important role in providing food and generate high income in many developing countries but the abundance of ammonia discharged from aquaculture wastewater gives the problem to the environment. This study focused on the extraction of hydroxyapatite (HAp) from fish scales and its modification with rice husk to produce bio-adsorbent for ammonia removal from aquaculture wastewater. The comparison has been made for the HAp preparation via microwave irradiation, alkaline heat treatment, and thermal decomposition method. X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) were used to analyze the surface chemistry and crystallinity of HAp, respectively. While the morphology of the HAp was observed under a Scanning Electron Microscope (SEM). Hydroxyapatite extracted via thermal decomposition method shows the best performance about 79% of ammonia removal at 210 min contact time which selected for coating agent of rice husk (RH/HAp) and was successfully removed 84% at 60 min saturation time. The result shows thermal decomposition is the best technique to extract HAp from fish scales and its integration with rice husk exhibited a better performance of bio-adsorbent. The findings of this study provide useful fundamental knowledge and platform for the development and improvement of aquaculture wastewater treatment system in the future.

scholarly journals Synthesis of Transition Metal Dichalcogenides based hybrid nanostructures by thermal decomposition method

2021 ◽  
Vol 2070 (1) ◽  
pp. 012095
Author(s):  
Melbin Baby ◽  
K. Rajeev Kumar
Keyword(s):  
Electron Microscopy ◽  
Thermal Decomposition ◽  
Decomposition Method ◽  
Transition Metal Dichalcogenides ◽  
Hybrid Nanostructures ◽  
Hybrid Nanostructure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Thermal Decomposition Method ◽  
Metal Dichalcogenides

Abstract In this work, we report synthesis of hybrid nanostructures of Transition Metal Dichalcogenides via thermal decomposition method. Ammonium tetrathiomolybdate was used as not only growth templates but also as starting precursor for synthesis of hybrid nanostructures. The conditions for the synthesizing method were optimized using electron microscopy and x-ray diffraction. In this hybrid nanostructure synthesis, it was found that MoO3 nanorods are interspersed on exfoliated MoS2 nanosheets. The structural and optical properties of the hybrid nanostructure were investigated using transmission electron microscopy (TEM), Scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy and Ultraviolet Visible spectrophotometry (UV-VIS). The hybrid nanostructure of MoO3 on MoS2 shows a band gap of 2.2 eV. It was also found that by tuning the preparation parameters viz temperature of heating and time of heating, the composition of the hybrid nanostructure can be varied.

Phase Transition and Microstructure Development of BaTiO3 by Thermal Development of BaTiO3 by Thermal Decomposition Method

2018 ◽  
Vol 879 ◽  
pp. 13-17
Author(s):  
Sudarath Suntaropas ◽  
Panakamon Thonglor ◽  
Naphat Albutt
Keyword(s):  
Thermal Decomposition ◽  
Decomposition Method ◽  
Sintering Temperature ◽  
Particle Growth ◽  
Microstructure Development ◽  
X Ray Diffraction ◽  
X Ray ◽  
Thermal Decomposition Method ◽  
Thermal Development ◽  
Major Factors

The thermal decomposition was used to prepare BaTiO3 powders. Using BaCO3 and TiO2 powders as precursors and heat treatment in the temperature range of 600-1000 °C for 6 hr. The final product (BaTiO3) proceeds through a trace amount of Ba2TiO4. The phase transformation was investigated by X-ray diffraction (XRD) as a function of sintering temperature. The results show that the microstructures of BaTiO3 were developed during sintering at different temperature. In additional, the particle growth of BaCO3 and TiO2 are the major factors to affect of the particle growth mechanism.

XPS Spectra and Optical Reflectivity of Yttrium Stabilised Zirconia

1992 ◽  
Vol 293 ◽  
Author(s):  
P. Camagni ◽  
L.E. Depero ◽  
F. Parmigiani ◽  
G. Samoggia ◽  
L. Sangaletri ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Synchrotron Radiation ◽  
Energy Range ◽  
Single Crystals ◽  
Valence Band ◽  
Conduction Band ◽  
Photoelectron Spectroscopy ◽  
Electron Excitation ◽  
Xps Spectra ◽  
X Ray

AbstractX-ray photoelectron spectroscopy measurements and synchrotron radiation reflectivity and measurements in the photon energy range between 5eV and 30 eV are reported for yttrium stabilised zirconia single crystals. From the present data some behaviour of the valence band and conduction band electronic structure are elucidated. Two features present in the valence band XPS spectra, not explained on the basis of one-clectron theory, are tentatively assigned to simultaneous two electron excitation.

scholarly journals The Synthesis of NiO/TiO2Heterostructures and Their Valence Band Offset Determination

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Z. H. Ibupoto ◽  
M. A. Abbasi ◽  
X. Liu ◽  
M. S. AlSalhi ◽  
M. Willander
Keyword(s):  
Valence Band ◽  
Conduction Band ◽  
Photoelectron Spectroscopy ◽  
Glass Substrate ◽  
Band Offset ◽  
Valence Band Offset ◽  
X Ray ◽  
Conduction Band Offset ◽  
P Type ◽  
Fto Glass

In this work, a heterojunction based on p-type NiO/n-type TiO2nanostructures has been prepared on the fluorine doped tin oxide (FTO) glass substrate by hydrothermal method. Scanning electron microscopy (SEM) and X-Ray diffraction techniques were used for the morphological and crystalline arrays characterization. The X-ray photoelectron spectroscopy was employed to determine the valence-band offset (VBO) of the NiO/TiO2heterojunction prepared on FTO glass substrate. The core levels of Ni 2p and Ti 2p were utilized to align the valence-band offset of p-type NiO/n-type TiO2heterojunction. The valence band offset was found to be∼0.41 eV and the conduction band was calculated about∼0.91 eV. The ratio of conduction band offset and the valence-band offset was found to be 2.21.

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