Improved Functional Capabilities of Quasi-Two-Dimensional Tungsten Oxide Nanostructures

2016 ◽  
Vol 689 ◽  
pp. 55-59
Author(s):  
Serge Zhuiykov

Electrical properties and morphology of orthorhombic β–WO3 nano-flakes with thickness of ~7-9 nm were investigated at the nanoscale using energy dispersive X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and current sensing force spectroscopy atomic force microscopy (CSFS-AFM, or PeakForce TUNATM). CSFS-AFM analysis established good correlation between the topography of the developed nanostructures and various features of WO3 nano-flakes synthesized via a two-step sol-gel-exfoliation method. It was determined that β–WO3 nano-flakes annealed at 550°C possess distinguished and exceptional thickness-dependent properties in comparison with the bulk, micro- and nano-structured WO3 synthesized at alternative temperatures.

2015 ◽  
Vol 08 (01) ◽  
pp. 1550007 ◽  
Author(s):  
Serge Zhuiykov ◽  
Eugene Kats ◽  
Tomoaki Sato ◽  
Hiroshi Ikeda ◽  
Norio Miura

Quasi-two-dimensional (Q2D) Nb 2 O 5 nanoflakes were synthesized by combined sol–gel/exfoliation method with the average thickness of 10–25 nm. Their structural, surface- and electro-chemical properties were closely studied and analyzed by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), conductive atomic force microscopy (AFM), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy techniques.


2011 ◽  
Vol 356-360 ◽  
pp. 574-578
Author(s):  
Xiao Jing Li ◽  
Guan Jun Qiao ◽  
Jin Ren Ni

Nanometer titanium dioxide films supported on glass, quartz, molybdenum, and aluminum were prepared by sol-gel method. The loaded titanium dioxide films were characterized by atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and photocatalytic degradation of aqueous crystal violet. The titanium dioxide films supported on different substrates were all composed of polycrystalline nanoparticles, which belonged to single-phase anatase, and displayed different morphology after sintering at 773 K for 1 h. Some elements in the substrate made of noncrystal appeared on the surface of titanium dioxide films. The experiment about basic crystal violet degradation displayed the photocatalysis activity of titanium oxide films supported on the molybdenum was better.


2003 ◽  
Vol 780 ◽  
Author(s):  
C. Essary ◽  
V. Craciun ◽  
J. M. Howard ◽  
R. K. Singh

AbstractHf metal thin films were deposited on Si substrates using a pulsed laser deposition technique in vacuum and in ammonia ambients. The films were then oxidized at 400 °C in 300 Torr of O2. Half the samples were oxidized in the presence of ultraviolet (UV) radiation from a Hg lamp array. X-ray photoelectron spectroscopy, atomic force microscopy, and grazing angle X-ray diffraction were used to compare the crystallinity, roughness, and composition of the films. It has been found that UV radiation causes roughening of the films and also promotes crystallization at lower temperatures.Furthermore, increased silicon oxidation at the interface was noted with the UVirradiated samples and was shown to be in the form of a mixed layer using angle-resolved X-ray photoelectron spectroscopy. Incorporation of nitrogen into the film reduces the oxidation of the silicon interface.


2013 ◽  
Vol 28 (2) ◽  
pp. 68-71 ◽  
Author(s):  
Thomas N. Blanton ◽  
Debasis Majumdar

In an effort to study an alternative approach to make graphene from graphene oxide (GO), exposure of GO to high-energy X-ray radiation has been performed. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM) have been used to characterize GO before and after irradiation. Results indicate that GO exposed to high-energy radiation is converted to an amorphous carbon phase that is conductive.


2019 ◽  
Vol 13 (26) ◽  
pp. 171-177
Author(s):  
Ban M. Al-Shabander

Titanium dioxide nanorods have been prepared by sol-gel templatemethod. The structural and surface morphology of the TiO2 nanorods wasinvestigated by X-ray diffraction (XRD) and atomic force microscopy(AFM), it was found that the nanorods produced were anatase TiO2 phase.The photocatalytic activity of the TiO2 nanorods was evaluated by thephoto degradation of methyl orange (MO). The relatively higherdegradation efficiency for MO (D%=78.2) was obtained after 6h of exposedto UV irradiation.


2012 ◽  
Vol 151 ◽  
pp. 314-318
Author(s):  
Ching Fang Tseng ◽  
Cheng Hsing Hsu ◽  
Chun Hung Lai

This paper describes microstructure characteristics of MgAl2O4 thin films were deposited by sol-gel method with various preheating temperatures and annealing temperatures. Particular attention will be paid to the effects of a thermal treatment in air ambient on the physical properties. The annealed films were characterized using X-ray diffraction. The surface morphologies of treatment film were examined by scanning electron microscopy and atomic force microscopy. At a preheating temperature of 300oC and an annealing temperature of 700oC, the MgAl2O4 films with 9 μm thickness possess a dielectric constant of 9 at 1 kHz and a dissipation factor of 0.18 at 1 kHz.


2013 ◽  
Vol 20 (01) ◽  
pp. 1350006 ◽  
Author(s):  
PARTHASARATHI BERA ◽  
H. SEENIVASAN ◽  
K. S. RAJAM

Co–W alloy coatings were deposited with direct current (DC) and pulse current (PC) electrodeposition methods using gluconate bath at pH5 and characterized by X-ray diffraction, field emission scanning electron microscopy, atomic force microscopy, differential scanning calorimetry (DSC) and X-ray photoelectron spectroscopy (XPS). DSC studies hint at the possibility of formation of metallic glasses. Detailed XPS studies of these alloy coatings have been carried out to compare elemental states and composition of Co and W in DC and PC electrodeposited alloys. DC-plated alloy has significant amount of Co and W metal along with their respective oxidized species. In contrast, mainly oxidized metals are present in the following layers of as-deposited coatings prepared with PC plating. Concentration of Co metal is observed to increase during sputtering, whereas there is no change in W6+ concentration. Microhardness measurement of all the Co–W coatings shows higher hardness compared to Co metal and 1:1 and 1:4 PC electrodeposited coatings show little higher hardness compared to 1:2 PC electrodeposited coating.


Clay Minerals ◽  
2009 ◽  
Vol 44 (4) ◽  
pp. 455-468 ◽  
Author(s):  
P. Somelar ◽  
K. Kirsimäe ◽  
J. Środoń

AbstractThe composition and particle morphology of diagenetic mixed-layer illite-smectite (I-S) in the shallow buried Ordovician Kinnekulle K-bentonite were studied to understand the process of illitization in the Baltic Basin. The same K-bentonite bed from 12 different locations in the Basin was sampled and analysed by means of X-ray diffraction (XRD), atomic-force microscopy (AFM) and K-Ar dating. Illite-smectite in the samples was identified as a highly illitic R1 type illite-smectite vermiculite (high-charge smectite) mixed-layer mineral with 63–78% illitic layers. Illite-smectite was characterized by log-normally distributed thin particles with an area-weighted mean thickness varying from 1.9 to 3.6 nm and 2.1 to 3.8 nm by XRD-PVP and AFM analysis, respectively. The K-Ar diagenetic ages of the mixed-layer minerals suggest an illitization age of 370 to 420 Ma that agrees with the latest phase of the Caledonian orogeny. Illitization of the Kinnekulle bentonite was probably driven by the intrusion of K-rich fluids.


2013 ◽  
Vol 787 ◽  
pp. 65-70
Author(s):  
Xin Zhang ◽  
Lei Mao ◽  
Jing Ma

Ultrathin silica films were grown on polyimide substrates using surface sol-gel method and the film growth process was characterized by ellipsometry, atomic force microscopy, X-ray photoelectron spectroscopy, Fourier transformed infrared spectroscopy. The polyimide substrates were pretreated by chemical process for promoting the growth of silica film. On the modified polymide surface, the growth of silica films shows an island-like growth type, but not a lay-by-lay process. Moreover, the deposited silica films are not a strict SiO2 film.


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