Solvothermal/ Hydrothermal Synthesis of Metal Oxides and Metal Powders with and without Microwaves

2010 ◽  
Vol 65 (8) ◽  
pp. 1033-1037 ◽  
Author(s):  
Sridhar Komarneni ◽  
Young Dong Noh ◽  
Joo Young Kim ◽  
Seok Han Kim ◽  
Hiroaki Katsuki

Anatase and Ca, Sr and Ca0.5Sr0.5 hydroxyapatites were synthesized by conventional-hydrothermal (C-H) as well asmicrowave-hydrothermal (M-H)methods.Microwave-assisted reactions led to accelerated syntheses of anatase but no such acceleration of reactions could be detected with the syntheses of hydroxyapatites because the crystallization of the latter materials occurred at very low temperature. Cu and Au metal powders were produced by using glucose, fructose or sucrose as reducing agents under C-H conditions at 160 ℃, where fructose and sucrose were found to be stronger reducing agents than glucose. The crystallinity of all the powders was characterized by powder X-ray diffraction, and morphology and particle sizes were determined by scanning or transmission electron microscopy

2013 ◽  
Vol 750-752 ◽  
pp. 217-220
Author(s):  
Li Jin Feng ◽  
Rong Ma ◽  
Xiu Hua Li ◽  
Xu Chun Song

In the present paper, the WO3 nanoparticles were fabricated via a hydrothermal treatment. The products are characterized in detail by multiform techniques: transmission electron microscopy, X-ray diffraction. The results show that products are WO3 nanoparticles with diameter of about 100-150 nm. Electrochemistry properties of the prepared WO3 nanoparticles was characterized by cyclic voltammetry. Cyclic voltammetry results indicate that WO3 nanoparticles exhibits a remarkable electrochemical activity for hydrogen intercalation. The reason for electrochemical activity of WO3 nanoparticles is attributed to the formation of HxWO3 by hydrogen intercalation/de-intercalation into/out of the tungsten oxide.


2010 ◽  
Vol 663-665 ◽  
pp. 100-103
Author(s):  
Zhen Ni Du ◽  
Yong Cai Zhang ◽  
Zhi You Xu ◽  
Ming Zhang

The synthesis of hexagonal phase Zn1-xMnxS (x = 0–0.05) nanorods was achieved by hydrothermal treatment of zinc manganese diethyldithiocarbamates (Zn1-xMnx-(DDTC)2, x=0–0.05) in 40 mass % hydrate hydrazine aqueous solution at 180 °C for 12 h. The structure, composition and optical property of the obtained products were characterized by X-ray diffraction, energy dispersive X-ray spectroscopy, transmission electron microscopy and UV-vis diffuse reflectance spectra.


2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
L. M. Artem ◽  
D. M. Santos ◽  
A. R. De Andrade ◽  
K. B. Kokoh ◽  
J. Ribeiro

This work consisted in the preparation of platinum-based catalysts supported on carbon (Vulcan XC-72) and investigation of their physicochemical and electrochemical properties. Catalysts of the C/Pt-Ni-Sn-Me (Me = Ru or Ir) type were prepared by the Pechini method at temperature of350∘C. Four different compositions were homemade: C/Pt60Sn10Ni30, C/Pt60Sn10Ni20Ru10, C/Pt60Sn10Ni10Ru20, and C/Pt60Sn10Ni10Ir20. These catalysts were electrochemically and physically characterized by cyclic voltammetry (CV), chronoamperometry (CA) in the presence of glycerol 1.0 mol dm-3, X-ray diffraction (XRD), and high-resolution transmission electron microscopy (HRTEM). XRD results showed the main peaks of face-centered cubic Pt. The particle sizes obtained from XRD and HRTEM experiments were close to values ranging from 3 to 8.5 nm. The CV results indicate behavior typical of Pt-based catalysts in acid medium. The CV and CA data reveal that quaternary catalysts present the highest current density for the electrooxidation of glycerol.


2013 ◽  
Vol 385-386 ◽  
pp. 16-18
Author(s):  
Yan Zhong Zhen ◽  
Dan Jun Wang ◽  
Feng Fu ◽  
Gang Lin Xue

A novel mixed metal molybdates, Zn2(MoO4)(SeO3) 1 has been synthesized by a simple hydrothermal process. Samples obtained are characterized using powder and single crystal X-ray diffraction (XRD), transmission electron microscopy (TEM). Furthermore, the photocatalytic performances of samples obtained are investigated for degradation of RhB under visible light irradiation. photocayalysis experimental result has illustrated that the compound exhibits good photocatalysis.


2012 ◽  
Vol 557-559 ◽  
pp. 489-492
Author(s):  
Zhi Xin Chen ◽  
Ya Zhen Ye ◽  
Han Jie Huang ◽  
Guang Can Xiao ◽  
Yun Hui He

The tetragonal phase CuInS2 nanoparticles were synthesized by the reaction of Cu(Ac)2, InCl3·4H2O and thioacetamide by hydrothermal method at 200 °C for 6 h in pH 1. The products were characterized by X-ray diffraction, energy-dispersive X-ray spectrum, X-ray photoelectron spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. Experimental results indicate that reaction temperature and the pH of solution are the important factors in the formation of CuInS2. The SEM and TEM results illuminated that the CuInS2 was composed of so many nanoparticles.


2012 ◽  
Vol 463-464 ◽  
pp. 777-780 ◽  
Author(s):  
Lin Lin Yang ◽  
Yong Gang Wang ◽  
Yu Jiang Wang

Single-crystal Na0.5Bi0.5TiO3 nanoflakes have been successfully synthesized at 160°C with 8M NaOH by a hydrothermal method assisted by sodium nitrate. The as-prepared samples were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The presence of sodium nitrate was found to play an important role in the growth of single-crystal Na0.5Bi0.5TiO3 nanoflakes.


Author(s):  
R. Gronsky

The phenomenon of clustering in Al-Ag alloys has been extensively studied since the early work of Guinierl, wherein the pre-precipitation state was characterized as an assembly of spherical, ordered, silver-rich G.P. zones. Subsequent x-ray and TEM investigations yielded results in general agreement with this model. However, serious discrepancies were later revealed by the detailed x-ray diffraction - based computer simulations of Gragg and Cohen, i.e., the silver-rich clusters were instead octahedral in shape and fully disordered, atleast below 170°C. The object of the present investigation is to examine directly the structural characteristics of G.P. zones in Al-Ag by high resolution transmission electron microscopy.


Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 611
Author(s):  
Celia Marcos ◽  
María de Uribe-Zorita ◽  
Pedro Álvarez-Lloret ◽  
Alaa Adawy ◽  
Patricia Fernández ◽  
...  

Chert samples from different coastal and inland outcrops in the Eastern Asturias (Spain) were mineralogically investigated for the first time for archaeological purposes. X-ray diffraction, X-ray fluorescence, transmission electron microscopy, infrared and Raman spectroscopy and total organic carbon techniques were used. The low content of moganite, since its detection by X-ray diffraction is practically imperceptible, and the crystallite size (over 1000 Å) of the quartz in these cherts would be indicative of its maturity and could potentially be used for dating chert-tools recovered from archaeological sites. Also, this information can constitute essential data to differentiate the cherts and compare them with those used in archaeological tools. However, neither composition nor crystallite size would allow distinguishing between coastal and inland chert outcrops belonging to the same geological formations.


Author(s):  
Eric O'Quinn ◽  
Cameron Tracy ◽  
William F. Cureton ◽  
Ritesh Sachan ◽  
Joerg C. Neuefeind ◽  
...  

Er2Sn2O7 pyrochlore was irradiated with swift heavy Au ions (2.2 GeV), and the induced structural modifications were systematically examined using complementary characterization techniques including transmission electron microscopy (TEM), X-ray diffraction...


Crystals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 456
Author(s):  
Fahad A. Alharthi ◽  
Hamdah S. Alanazi ◽  
Amjad Abdullah Alsyahi ◽  
Naushad Ahmad

This study demonstrated the hydrothermal synthesis of bimetallic nickel-cobalt tungstate nanostructures, Ni-CoWO4 (NCW-NPs), and their phase structure, morphology, porosity, and optical properties were examined using X-ray Diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), Scanning electron microscopy- energy dispersive X-ray spectroscopy (SEM-EDS), high resolution Transmission electron microscopy (HR-TEM), Brunauer-Emmett-Teller (BET) and Raman instruments. It was found that as-calcined NCW-NPs have a monoclinic phase with crystal size ~50–60 nm and is mesoporous. It possessed smooth, spherical, and cubic shape microstructures with defined fringe distance (~0.342 nm). The photocatalytic degradation of methylene blue (MB) and rose bengal (RB) dye in the presence of NCW-NPs was evaluated, and about 49.85% of MB in 150 min and 92.28% of RB in 90 min degraded under visible light. In addition, based on the scavenger’s study, the mechanism for photocatalytic reactions is proposed.


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