scholarly journals SINTESIS DAN KARAKTERISASI PARTIKEL NANOSPERIK TIO2 MELALUI METODE HIDROTERMAL GELOMBANG MIKRO

2014 ◽  
Vol 7 (2) ◽  
pp. 101
Author(s):  
Amelia Amir ◽  
Emriadi ◽  
Syukri Arief ◽  
Kazuhiro Manseki ◽  
Takashi Sugiura
Keyword(s):  
Ammonium Hydroxide ◽  
Structure Directing Agent ◽  
Microwave Hydrothermal ◽  
Transmission Electron ◽  
Tetra Methyl Ammonium Hydroxide ◽  
Titanium Tetra Isopropoxide ◽  
Microwave Hydrothermal Method ◽  
Size Of Particles ◽  
Xrd Patterns ◽  
Good Agreement

 ABSTRACTSimple synthesis of nanospherical TiO2 by microwave hydrothermal method has beeninvestigated. Titanium tetra isopropoxide (TTIP) and tetra methyl ammonium hydroxide(TMAOH) were used as precursor. The crystal phase and microstructure were characterized byX-Ray Diffraction (XRD) and transmission electron microscopy (TEM) including selected areadiffraction (SAED). The presence of intense peak in the XRD patterns confirmed to anatase andin good agreement with SAED patterns. Nanospherical of particles were clearly seen in theTEM image and the size of particles was approximately 4-5 nm.Keywords : microwave hydrothermal, colloidal titanates, structure directing agent,nanospherical TiO2

High capacity VO2(B) nanostrips synthesized by microwave-hydrothermal method

2019 ◽  
Vol 12 (02) ◽  
pp. 1950004 ◽  
Author(s):  
Zi Yang ◽  
Yongchuan Liu ◽  
Feng Li ◽  
Qingya Yin ◽  
Youxin Lou ◽  
...  
Keyword(s):  
Hydrothermal Method ◽  
Coulombic Efficiency ◽  
High Capacity ◽  
Microwave Hydrothermal ◽  
Initial Discharge ◽  
Microwave Hydrothermal Method ◽  
Alignment Structure ◽  
Xrd Patterns ◽  
Discharge Capacities ◽  
Very High

VO2(B) nanostrips were synthesized by microwave-hydrothermal method. The XRD patterns show that VO2(B) nanostrips are pure metastable monoclinic phase. VO2(B) nanostrips, in length of 1.5–2[Formula: see text][Formula: see text]m, width of 200–400[Formula: see text]nm, and thickness of 10–20[Formula: see text]nm, present exposed (001) facets and parallel alignment structure. The VO2(B) nanostrips are composed of nanosheets with 2–5[Formula: see text]nm thickness. A very high initial discharge capacity of 318.3[Formula: see text]mAh[Formula: see text]g[Formula: see text] is obtained and the capacity of 100th cycle is 248.5[Formula: see text]mAh[Formula: see text]g[Formula: see text] (about 78.0% retention) at 50[Formula: see text]mA[Formula: see text]g[Formula: see text]. The capacity fades at about 4.08% per cycle for the first 10 cycles. After 10 cycles, the fading slows down to 0.32% per cycle. The rate performance shows the first discharge capacities of VO2(B) nanostrips are 249.6, 212.0, 181.8, 161.7, and 145.2[Formula: see text]mAh[Formula: see text]g[Formula: see text] at 0.1, 0.2, 0.4, 0.8, and 1.6[Formula: see text]A[Formula: see text]g[Formula: see text], respectively, with around 100% coulombic efficiency. Glycerol and microwave-hydrothermal method contribute to the shaping and thickness of VO2(B) nanostrips with the parallel alignment nanostructure, which directly improves the electrical properties of this material.

MICROWAVE HYDROTHERMAL SYNTHESIS OF RUTILE TiO2 NANORODS

2005 ◽  
Vol 19 (15n17) ◽  
pp. 2763-2768 ◽  
Author(s):  
GUOBIN MA ◽  
XIAONING ZHAO ◽  
JIANMIN ZHU
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
X Ray Diffraction ◽  
High Quality ◽  
X Ray ◽  
Microwave Hydrothermal ◽  
Transmission Electron ◽  
Microwave Hydrothermal Method ◽  
Scanning Electron

We present in this paper the synthesis of rutile TiO 2 nanorods using an efficient microwave hydrothermal method. The product was characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy, and the results indicated the growth of high quality rutile nanorods along the c-axis of rutile TiO 2 and the radial aggregation of them into spherical secondary nanoparticles.

Fine MCP Decapsulation Technology Development

2006 ◽  
Author(s):  
Jianwei Zhou ◽  
Wei Zheng ◽  
Taekoo Lee
Keyword(s):  
Chemical Etching ◽  
Etch Rate ◽  
Technology Development ◽  
New Technology ◽  
Ammonium Hydroxide ◽  
Mechanical Polishing ◽  
Technology Process ◽  
Tetra Methyl Ammonium Hydroxide ◽  
Die Surface

Abstract Multi-Chip Package (MCP) decapsulation is now becoming a rising problem. Because for traditional decapsulation method, acid can’t dissolve the top silicon die to expose the bottom die surface in MCP. It makes inspecting the bottom die in MCP is difficult. In this paper, a new MCP decapsulation technology combining mechanical polishing with chemical etching is introduced. This new technology can remove the top die quickly without damaging the bottom die using KOH and Tetra-Methyl Ammonium Hydroxide (TMAH). The technology process and relative application are presented. The factors that affect the KOH and TMAH etch rate are studied. The usage difference between the two etchant is discussed.

scholarly journals Hydrothermally Assisted Fabrication of TiO2-Fe3O4 Composite Materials and Their Antibacterial Activity

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4715
Author(s):  
Adam Kubiak ◽  
Marta Kubacka ◽  
Elżbieta Gabała ◽  
Anna Dobrowolska ◽  
Karol Synoradzki ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Composite Materials ◽  
Bet Surface Area ◽  
Molar Ratio ◽  
Oxide Content ◽  
Gram Positive ◽  
Gram Negative ◽  
Transmission Electron ◽  
Xrd Patterns ◽  
Oxide Composites

The TiO2-Fe3O4 composite materials were fabricated via the hydrothermal-assisted technique. It was determined how the molar ratio of TiO2 to Fe3O4 influences the crystalline structure and morphology of the synthesized composite materials. The effect of the molar ratio of components on the antibacterial activity was also analyzed. On the basis of XRD patterns for the obtained titanium(IV) oxide-iron(II, III) oxide composites, the two separate crystalline forms—anatase and magnetite —were observed. Transmission electron microscopy revealed particles of cubic and tetragonal shape for TiO2 and spherical for Fe3O4. The results of low-temperature nitrogen sorption analysis indicated that an increase in the iron(II, III) oxide content leads to a decrease in the BET surface area. Moreover, the superparamagnetic properties of titanium(IV) oxide-iron(II, III) oxide composites should be noted. An important aim of the work was to determine the antibacterial activity of selected TiO2-Fe3O4 materials. For this purpose, two representative strains of bacteria, the Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, were used. The titanium(IV) oxide-iron(II, III) oxide composites demonstrated a large zone of growth inhibition for both Gram-positive and Gram-negative bacteria. Moreover, it was found that the analyzed materials can be reused as antibacterial agents in three consecutive cycles with good results.

scholarly journals Upconversion Luminescence of Silica–Calcia Nanoparticles Co-doped with Tm3+ and Yb3+ Ions

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 937
Author(s):  
Katarzyna Halubek-Gluchowska ◽  
Damian Szymański ◽  
Thi Ngoc Lam Tran ◽  
Maurizio Ferrari ◽  
Anna Lukowiak
Keyword(s):  
Energy Transfer ◽  
Near Infrared ◽  
Upconversion Luminescence ◽  
Sol Gel ◽  
Emission Spectra ◽  
Transmission Electron ◽  
Characteristic Emission ◽  
Diffraction Patterns ◽  
Size Of Particles ◽  
Average Size

Looking for upconverting biocompatible nanoparticles, we have prepared by the sol–gel method, silica–calcia glass nanopowders doped with different concentration of Tm3+ and Yb3+ ions (Tm3+ from 0.15 mol% up to 0.5 mol% and Yb3+ from 1 mol% up to 4 mol%) and characterized their structure, morphology, and optical properties. X-ray diffraction patterns indicated an amorphous phase of the silica-based glass with partial crystallization of samples with a higher content of lanthanides ions. Transmission electron microscopy images showed that the average size of particles decreased with increasing lanthanides content. The upconversion (UC) emission spectra and fluorescence lifetimes were registered under near infrared excitation (980 nm) at room temperature to study the energy transfer between Yb3+ and Tm3+ at various active ions concentrations. Characteristic emission bands of Tm3+ ions in the range of 350 nm to 850 nm were observed. To understand the mechanism of Yb3+–Tm3+ UC energy transfer in the SiO2–CaO powders, the kinetics of luminescence decays were studied.

scholarly journals A complicated quasicrystal approximant ∊16 predicted by the strong-reflections approach

2010 ◽  
Vol 66 (1) ◽  
pp. 17-26 ◽  
Author(s):  
Mingrun Li ◽  
Junliang Sun ◽  
Peter Oleynikov ◽  
Sven Hovmöller ◽  
Xiaodong Zou ◽  
...  
Keyword(s):  
Electron Diffraction ◽  
Unit Cell ◽  
Space Groups ◽  
Inverse Fourier Transformation ◽  
Transmission Electron ◽  
Structure Factors ◽  
Precession Electron Diffraction ◽  
Density Map ◽  
Electron Density Map ◽  
Good Agreement

The structure of a complicated quasicrystal approximant ∊16 was predicted from a known and related quasicrystal approximant ∊6 by the strong-reflections approach. Electron-diffraction studies show that in reciprocal space, the positions of the strongest reflections and their intensity distributions are similar for both approximants. By applying the strong-reflections approach, the structure factors of ∊16 were deduced from those of the known ∊6 structure. Owing to the different space groups of the two structures, a shift of the phase origin had to be applied in order to obtain the phases of ∊16. An electron-density map of ∊16 was calculated by inverse Fourier transformation of the structure factors of the 256 strongest reflections. Similar to that of ∊6, the predicted structure of ∊16 contains eight layers in each unit cell, stacked along the b axis. Along the b axis, ∊16 is built by banana-shaped tiles and pentagonal tiles; this structure is confirmed by high-resolution transmission electron microscopy (HRTEM). The simulated precession electron-diffraction (PED) patterns from the structure model are in good agreement with the experimental ones. ∊16 with 153 unique atoms in the unit cell is the most complicated approximant structure ever solved or predicted.

Microstructure Characterization of Metal Mixed Oxides

MRS Advances ◽  
2017 ◽  
Vol 2 (64) ◽  
pp. 4025-4030 ◽  
Author(s):  
T. Kryshtab ◽  
H. A. Calderon ◽  
A. Kryvko
Keyword(s):  
Mixed Oxides ◽  
Profile Analysis ◽  
Atomic Resolution ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Reconstruction Procedure ◽  
Transmission Electron ◽  
Xrd Patterns ◽  
Co Precipitation

ABSTRACTThe microstructure of Ni-Mg-Al mixed oxides obtained by thermal decomposition of hydrotalcite-like compounds synthesized by a co-precipitation method has been studied by using X-ray diffraction (XRD) and atomic resolution transmission electron microscopy (TEM). XRD patterns revealed the formation of NixMg1-xO (x=0÷1), α-Al2O3 and traces of MgAl2O4 and NiAl2O4 phases. The peaks profile analysis indicated a small grain size, microdeformations and partial overlapping of peaks due to phases with different, but similar interplanar spacings. The microdeformations point out the presence of dislocations and the peaks shift associated with the presence of excess vacancies. The use of atomic resolution TEM made it possible to identify the phases, directly observe dislocations and demonstrate the vacancies excess. Atomic resolution TEM is achieved by applying an Exit Wave Reconstruction procedure with 40 low dose images taken at different defocus. The current results suggest that vacancies of metals are predominant in MgO (NiO) crystals and that vacancies of Oxygen are predominant in Al2O3 crystals.

Amorphous magnesium phosphate flower-like hierarchical nanostructures: microwave-assisted rapid synthesis using fructose 1,6-bisphosphate trisodium salt as an organic phosphorus source and application in protein adsorption

RSC Advances ◽  
2015 ◽  
Vol 5 (19) ◽  
pp. 14906-14915 ◽  
Author(s):  
Chao Qi ◽  
Ying-Jie Zhu ◽  
Bing-Qiang Lu ◽  
Jin Wu ◽  
Feng Chen
Keyword(s):  
Organic Phosphorus ◽  
Magnesium Phosphate ◽  
Rapid Synthesis ◽  
Hierarchical Nanostructures ◽  
Microwave Assisted ◽  
Microwave Hydrothermal ◽  
Microwave Hydrothermal Method ◽  
Phosphorus Source ◽  
Trisodium Salt ◽  
Fructose 1,6 Bisphosphate

Amorphous magnesium phosphate flower-like hierarchical nanostructures are synthesized using fructose 1,6-bisphosphate trisodium salt by the microwave hydrothermal method.

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