scholarly journals Photocatalytic Reduction of CO2Using TiO2-Graphene Nanocomposites

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
Jinghua Liu ◽  
Yinghua Niu ◽  
Xiong He ◽  
Jingyao Qi ◽  
Xin Li
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Raman Spectroscopy ◽  
Chemical Method ◽  
X Ray Diffraction ◽  
Graphene Nanocomposites ◽  
X Ray ◽  
Transmission Electron ◽  
Simple Chemical ◽  
Adsorption Desorption

TiO2-graphene (TiO2-RGO) nanocomposites were preparedviaa simple chemical method by using graphene oxide (GO) and TiO2nanoparticles as starting materials. The morphologies and structural properties of the as-prepared composites were characterized by X-ray diffraction, Raman spectroscopy, N2adsorption-desorption measurements, and transmission electron microscopy. TiO2-RGO nanocomposites exhibited great photocatalytic activity toward reduction of CO2into CH4(2.10 μmol g−1 h−1) and CH3OH (2.20 μmol g−1 h−1), which is attributed to the synergistic effect between TiO2and graphene.

Synthesis and Study the Properties of a Solar Cell of Gold Nanoparticles Prepared in a Simple Chemical Way

2021 ◽  
Vol 19 (11) ◽  
pp. 66-71
Author(s):  
Maithm A. Obaid ◽  
Suha A Fadaam ◽  
Osama S. Hashim
Keyword(s):  
Electron Microscopy ◽  
Gold Nanoparticles ◽  
Chemical Method ◽  
X Ray Diffraction ◽  
Structural And Optical Properties ◽  
Casting Method ◽  
X Ray ◽  
Transmission Electron ◽  
Simple Chemical ◽  
Scanning Electron

The aim of this study is to prepare gold nanoparticles by a simple chemical method at a temperature of 70°C. The solution was dried on glass basest by Casting method, the rate of five drops per sample At a temperature 100 C. Then the structural and optical properties have been confirmed by X-ray diffraction, scanning electron microscopy (SEM) and Transmission Electron microscope (TEM), Fourier Transform Infrared Spectroscopy (FTIR) and spectrum.

Optical properties and energy transfer processes in Tb3+-doped ZnSe quantum dots

2021 ◽  
Author(s):  
Nguyen Ca ◽  
N. D Vinh ◽  
Phan Van Do ◽  
N. T. Hien ◽  
Xuan Hoa Vu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Quantum Dots ◽  
Chemical Method ◽  
X Ray Diffraction ◽  
Wet Chemical Method ◽  
X Ray ◽  
Transfer Processes ◽  
Transmission Electron ◽  
Wet Chemical

Tb3+-doped ZnSe quantum dots (QDs) with Tb content in the range of 0.5 - 7% were successfully synthesized by a wet chemical method. X-ray diffraction (XRD) and transmission electron microscopy...

The structural changes of polycrystalline film C60/C70: Ni caused by Ni diffusion

1996 ◽  
Vol 11 (12) ◽  
pp. 3146-3151 ◽  
Author(s):  
E. Czerwosz ◽  
P. Byszewski ◽  
R. Diduszko ◽  
H. Wronka ◽  
P. Dluźewski ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Raman Spectroscopy ◽  
Structural Changes ◽  
Thermal Conditions ◽  
Vacuum Deposition ◽  
X Ray Diffraction ◽  
Polycrystalline Structure ◽  
X Ray ◽  
Transmission Electron

C60/C70: Ni films with 1.5 wt. % Ni concentration obtained by vacuum deposition under different thermal conditions have been investigated. The structural changes of the layers were investigated by transmission electron microscopy, electron and x-ray diffraction, and Raman spectroscopy. The polycrystalline structure was detected for the layers grown at approximately 450 K on the substrate. At elevated temperature and maintained temperature gradient on the substrate during the process, the changes of the layer's structure and the formation of Ni microcrystals were observed. The Ni microcrystals (5–10 nm in the diameter) and the elongated shapes dimensioned 10 × 150 nm were perceived.

Sol-gel processing of nanocrystalline haematite thin films

1997 ◽  
Vol 12 (6) ◽  
pp. 1441-1444 ◽  
Author(s):  
L. Armelao ◽  
A. Armigliato ◽  
R. Bozio ◽  
P. Colombo
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Raman Spectroscopy ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Single Particles ◽  
X Ray ◽  
Transmission Electron ◽  
Gel Processing

The microstructure of Fe2O3 sol-gel thin films, obtained from Fe(OCH2CH3)3, was investigated by x-ray diffraction (XRD), transmission electron microscopy (TEM), and Raman spectroscopy. Samples were nanocrystalline from 400 °C to 1000 °C, and the crystallized phase was haematite. In the coatings, the α–Fe2O3 clusters were dispersed as single particles in a network of amorphous ferric oxide.

Mesoporous TiO2 Prepared by Using Lac Red as Template：Synthesis, Characterization, and Adsorption of Gaseous Acetaldehyde

2013 ◽  
Vol 742 ◽  
pp. 448-451
Author(s):  
Ming Feng Wang ◽  
Tou Gen Liao ◽  
Bao Kun Zhu ◽  
Yao Wang ◽  
Yan Qing Duan ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Mesoporous Titania ◽  
X Ray Diffraction ◽  
High Adsorption ◽  
X Ray ◽  
Transmission Electron ◽  
Adsorption Desorption ◽  
Scanning Electron

Mesoporous TiO2 with anatase crystalline structure (MTiO2) has been synthesized by using Lac Red as template. The synthesized mesoporous titania samples were characterized by a combination of various physicochemical techniques, such as X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), N2 adsorption/desorption. It was found that without any external doping MTiO2 exhibited significant high adsorption abilities for adsorbing the gaseous acetaldehyde by the adsorption ratio of 39.15%.

Performance of CO2 Adsorption with MEA-AN Modified Solid Adsorbent

2013 ◽  
Vol 341-342 ◽  
pp. 13-17
Author(s):  
Xiao Yun Zhang ◽  
Hong Yan Qin ◽  
Xiu Xin Zheng ◽  
Shi Hu Yu ◽  
Wei Wu
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Pore Channel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solid Adsorbent ◽  
Satisfactory Performance ◽  
Transmission Electron ◽  
Ft Ir ◽  
Adsorption Desorption

CO2solid adsorbent was prepared through impregnating acrylonitrile (AN) modified monoethanolamine (MEA) into structurally disordered mesoporous silica (M) pore channel. Its structure was characterized by X-ray diffraction characterization (XRD), N2adsorption-desorption tests (BET), Transmission electron microscopy (TEM) and Fourier transform infrared (FT-IR). The capacity of CO2adsorption and desorption were measured and evaluated by comparison with MEA-impregnated material. The results showed that the capacity of M-MN-50 reached up to 125.8 mg·g-1and could desorb completely at the temperature of 40 °C by vacuum with 2.6 KPa. The hybrid material exhibited satisfactory performance during 10 turnovers.

Electron beam-induced surface modification and nano-engineering of carbon nanotubes: Single-walled and multiwalled

2006 ◽  
Vol 21 (12) ◽  
pp. 3109-3123 ◽  
Author(s):  
S. Gupta ◽  
R.J. Patel ◽  
R.E. Giedd
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Raman Spectroscopy ◽  
Electron Beam ◽  
Electron Microscope ◽  
High Resolution ◽  
Band Intensity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

Influence of low and medium energy electron beam (E-beam) irradiation on the single-walled (SW) and multiwalled (MW) carbon nanotube films grown by microwave chemical vapor deposition are investigated. These films were subjected to electron beam energy of 50 keV from scanning electron microscope for 2.5, 5.5, 8.0, and 15 h and 100, 200, and 300 keV from transmission electron microscope electron gun for a few minutes to approximately 2 h continuously. To assess the surface modifications/structural degradation, the films were analyzed prior to and post-irradiation using x-ray diffraction and micro-Raman spectroscopy in addition to in situ monitoring by scanning and high-resolution transmission electron microscopy. A minimal increase in intertube or interplanar spacing (i.e., d002) for MW nanotubes ranging from 3.25–3.29 Å (∼3%) can be analogized to change in c-axis of graphite lattice due to thermal effects measured using x-ray diffraction. Resonance Raman spectroscopy revealed that irradiation generated defects in the lattice evaluated through variation of: the intensity of radial breathing mode (RBM), intensity ratio of D to G band (ID/IG), position of D and G bands and their harmonics (D* and G*). The increase in the defect-induced D band intensity, quenching of RBM intensity, and only a slight increase in G band intensity are some of the implications. The MW nanotubes tend to reach a state of saturation for prolonged exposures, while SW transforming semiconducting to quasi-metallic character. Softening of the q = 0 selection rule is suggested as a possible way to explain these results. It is also suggestive that knock-on collision may not be the primary cause of structural degradation, rather a local gradual reorganization, i.e., sp2+δ ⇔ sp2+δ, sp2 C seems quite possible. Experiments showed that with extended exposures, both kinds of nanotubes displayed various local structural instabilities including pinching, graphitization/amorphization, and forming intra-molecular junction (IMJ) within the area of electron beam focus possibly through amorphous carbon aggregates. They also displayed curling and closure forming nano-ring and helix-like structures while mending their dangling bonds. High-resolution transmission electron microscopy electrons corroborated these conclusions. Manufacturing of nanoscale structures “nano-engineering” of carbon-based systems is tentatively ascribed to irradiation-induced solid-state phase transformation, in contrast to conventional nanotube synthesis from the gas phase.

Characteristics of titanium nitride films grown by pulsed laser deposition

1996 ◽  
Vol 11 (6) ◽  
pp. 1458-1469 ◽  
Author(s):  
R. Chowdhury ◽  
R. D. Vispute ◽  
K. Jagannadham ◽  
J. Narayan
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Raman Spectroscopy ◽  
Titanium Nitride ◽  
Room Temperature ◽  
Room Temperature Resistivity ◽  
X Ray Diffraction ◽  
Tin Films ◽  
X Ray ◽  
Transmission Electron

Laser physical vapor deposition (LPVD) has been used to grow titanium nitride films on hydrogen-terminated silicon(100) substrates at deposition temperatures ranging from room temperature to 600 °C. A pulsed KrF excimer laser (λ = 248 nm, τ = 25 ns) was used with the deposition chamber maintained at a base pressure of 10−7 Torr prior to deposition. Different properties of the films were investigated by x-ray diffraction, Auger electron spectroscopy, Raman spectroscopy, optical, scanning, and high resolution transmission electron microscopy, and measurement of electrical resistivity. When the substrate temperature was low (at and below 500 °C), oxygen atoms from the residual gases were incorporated in the films. The microstructures and resistivities of TiN films were found to be strongly dependent on the temperature of the silicon substrates. The TiN films deposited at 600 °C were oxygen-free, as observed from Auger analysis, and the room temperature resistivity was found to be 14–15 μΩ-cm. Raman spectroscopy of the films showed that the nitrogen-related optical phonon peak increased with deposition temperature in comparison with the titanium-related acoustic peak. Transmission electron microscopy and x-ray diffraction analyses showed that the films were polycrystalline at low temperature with grain size ranging from 300–600 Å, depending on the temperature of the substrate. At 600 °C, the films were found to be single crystals with occasional presence of dislocation loops. The spacing of Moiré fringes in TiN/Si samples deposited at 600 °C established the nearly periodic elastic strain field extending into the TiN and Si at the interface. Although there exists a large misfit between TiN and Si (24.6%), the epitaxial growth of TiN films on Si(100) substrates was explained by means of domain-matched epitaxy with a 4-to-3 match in unit cells for TiN/Si structure, giving rise to a residual lattice misfit of only 4%.

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