scholarly journals Carbonitriding reactions of diatomaceous earth: phase evolution and reaction mechanisms

2006 ◽  
Vol 71 (6) ◽  
pp. 677-683 ◽  
Author(s):  
Branko Matovic ◽  
Aleksandra Saponjic ◽  
Snezana Boskovic
Keyword(s):  
Reaction Mechanisms ◽  
Carbothermal Reduction ◽  
Diatomaceous Earth ◽  
Phase Evolution ◽  
Raw Material ◽  
Low Temperature Synthesis ◽  
Temperature Synthesis ◽  
X Ray ◽  
Oxide Powders ◽  
Effective Source

The possibility of using diatomaceous earth as Si precursor for low temperature synthesis of non-oxide powders by carbothermal reduction-nitridation was studied. It was found that carbonitriding reactions produce phases of the Si-Al-O-N system. Already at 1300 ?C, nanosized non-oxide powders were obtained. The comparatively low reaction temperatures is attributred to the nano-porous nature of the raw material. The evolution of crystalline phases proceeded via many intermediate stages. The powders were characterized by X-ray and SEM investigations. The results showed that diatomaceous earth can be a very effective source for obtaining non-oxide powders.

scholarly journals Low-Temperature Synthesis of Solution Processable Carbon Nitride Polymers

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1646
Author(s):  
Junyi Li ◽  
Neeta Karjule ◽  
Jiani Qin ◽  
Ying Wang ◽  
Jesús Barrio ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Carbon Nitride ◽  
Spatial Organization ◽  
Surface Display ◽  
Liquid Media ◽  
Low Temperature Synthesis ◽  
Temperature Synthesis ◽  
X Ray ◽  
N2 Atmosphere ◽  
Carbon Nitride Materials

Carbon nitride materials require high temperatures (>500 °C) for their preparation, which entails substantial energy consumption. Furthermore, the high reaction temperature limits the materials’ processability and the control over their elemental composition. Therefore, alternative synthetic pathways that operate under milder conditions are still very much sought after. In this work, we prepared semiconductive carbon nitride (CN) polymers at low temperatures (300 °C) by carrying out the thermal condensation of triaminopyrimidine and acetoguanamine under a N2 atmosphere. These molecules are isomers: they display the same chemical formula but a different spatial distribution of their elements. X-ray photoelectron spectroscopy (XPS) experiments and electrochemical and photophysical characterization confirm that the initial spatial organization strongly determines the chemical composition and electronic structure of the materials, which, thanks to the preservation of functional groups in their surface, display excellent processability in liquid media.

scholarly journals Low temperature synthesis and characterization of Mn3O4 nanoparticles

2007 ◽  
Vol 5 (1) ◽  
pp. 169-176 ◽  
Author(s):  
Abdülhadi Baykal ◽  
Yüksel Köseoğlu ◽  
Mehmet Şenel
Keyword(s):  
Particle Size ◽  
Infrared Spectroscopy ◽  
Low Temperature ◽  
Synthesis And Characterization ◽  
Low Temperature Synthesis ◽  
Temperature Synthesis ◽  
X Ray ◽  
Peak Broadening ◽  
Mn3o4 Nanoparticles

AbstractHeating hydrous manganese (II) hydroxide gel at 85 °C for 12 hours produces Mn3O4 nanoparticles. They were characterized by X-ray powder diffraction (XRD) and infrared spectroscopy (FTIR). The particle size estimated from the SEM and X-ray peak broadening is approximately 32 nm, showing them to be nanocrystalline. EPR measurements confirm a typical Mn2+signal with a highly resolved hyperfine structure.

Low-Temperature Synthesis of Nano-Crystalline ZnTiO3 Powders by Aqueous Sol-Gel Process

2014 ◽  
Vol 543-547 ◽  
pp. 3741-3744
Author(s):  
Quan Jing Mei ◽  
Cong Ying Li ◽  
Jing Dong Guo ◽  
Gui Wang ◽  
Hai Tao Wu
Keyword(s):  
Sol Gel ◽  
Zinc Nitrate ◽  
X Ray Diffraction ◽  
Low Temperature Synthesis ◽  
Temperature Synthesis ◽  
Calcination Process ◽  
X Ray ◽  
Nano Crystalline ◽  
Transmission Electron ◽  
Sol Gel Process

The ecandrewsite-type ZnTiO3was successfully synthesized by the aqueous sol-gel method using TiO2dioxide and zinc nitrate as starting materials instead of expensive organic solvent and metal alkoxides. The as-prepared nanopowders were characterized by X-ray diffraction (XRD), differential thermal analysis (DTA) and transmission electron microscopy (TEM), respectively. The results showed that the calcination process of gel consisted of a series of oxidation and combustion reactions, accompanied by significantly exothermal effects. Highly reactive nanosized ZnTiO3powders were successfully obtained at 850 °C with particle size ~50 nm. By comparison, the aqueous sol-gel process was the most effective and least expensive technique used for the preparation of ZnTiO3nanopowders.

Low Temperature Synthesis of Plasma Teos SiO2

1996 ◽  
Vol 446 ◽  
Author(s):  
T. Itani ◽  
S. Fukuyama
Keyword(s):  
Reaction Mechanisms ◽  
Plasma Reactor ◽  
Substrate Surface ◽  
Condensation Reaction ◽  
Excitation Frequency ◽  
Elimination Reaction ◽  
Film Properties ◽  
Low Temperature Synthesis ◽  
Temperature Synthesis ◽  
Precursor Molecules

AbstractIn this study, we investigated the deposition temperature's affect on TEOS based Si02 properties and reaction mechanisms while changing the excitation frequency. We used a parallel-plate plasma reactor, and either 100 kHz or 13.56 MHz radio frequency to generate plasma. We found that 100 kHz plasma promotes SiO formation and improves the film properties at low deposition temperatures. We assume this to be due to the supplement of higher energy ions to the substrate surface in 100 kHz plasma. This in turn promotes the elimination reaction (condensation reaction) of OH that links to Si atoms as a terminator of surface SiO networks or precursor molecules.

Low Temperature Synthesis and Luminescent Properties of Ca2SnO4: Eu3

2010 ◽  
Vol 136 ◽  
pp. 14-17 ◽  
Author(s):  
Yu Zhong Li ◽  
Xiao Chun Zhou
Keyword(s):  
Low Temperature ◽  
Spherical Shape ◽  
Luminescent Properties ◽  
Xrd Analysis ◽  
Electric Dipole Transition ◽  
Low Temperature Synthesis ◽  
Temperature Synthesis ◽  
X Ray ◽  
Emission Transition ◽  
Red Emitting Phosphor

A novel red emitting phosphor, Ca2SnO4: Eu3+, was prepared by the low temperature solid state reaction. X-ray powder diffraction (XRD) analysis confirmed the formation of Ca2SnO4: Eu3+. Scanning electron-microscopy (SEM) observation indicated a narrow size distribution of about 500 nm for the particles with spherical shape. Under 396 nm excitation, the Ca2SnO4: Eu3+ phosphor exhibits novel red emission at about 613 nm which is assigned to the 5D0→7F2 electric-dipole transition. Furthermore, the emission transition 5D0→7F2 has been found to be more prominent over the normal orange emission transition 5D0→7F1.

THE INVESTIGATION ON STABILITY AND STRUCTURAL PROPERTIES OF COHESION-BASED NANOSTRUCTURES MATERIAL

2013 ◽  
Vol 27 (27) ◽  
pp. 1350153 ◽  
Author(s):  
ALI BAHARI ◽  
REZA GHOLIPUR ◽  
MARYAM DERAKHSHI
Keyword(s):  
Annealing Temperature ◽  
Sol Gel ◽  
Growth Mode ◽  
X Ray Diffraction ◽  
Low Temperature Synthesis ◽  
Temperature Synthesis ◽  
X Ray ◽  
Annealing Temperatures ◽  
Atomic Force ◽  
Transmission Electron

Styrene-doped ZrLaO y nanostructures were obtained by sol–gel method low-temperature synthesis. The nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscope (AFM) and transmission electron microscopy (TEM) techniques. The observation using SEM and TEM revealed that the ring-shaped nanostructures were very uniform. Further characterization using XRD disclosed that the cohesion of the samples was controllable with annealing temperatures in the range of 800–1500°C. Cohesion property was investigated for the samples. The cohesion increased when increasing the annealing temperature. This was linked to the reinforcement of the oxygen bound on the ZrLaO y nanostructures The shape of nanostructures showed a transformation from a ring-shaped growth mode to a hole-surfaced growth mode with increasing annealing temperature. The styrene-doped ZrLaO y nanostructures with controllable crystallinity will have great potential for various applications in fuel, cells, batteries, electronics devices and chemical sensors.

scholarly journals Comparative Study of Structural, Electrical, and Magnetic Behaviour of Ni-Cu-Zn Nanoferrites Sintered by Microwave and Conventional Techniques

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Biju Thangjam ◽  
Ibetombi Soibam
Keyword(s):  
Average Crystallite Size ◽  
Magnetic Behaviour ◽  
Low Temperature Synthesis ◽  
Temperature Synthesis ◽  
Precursor Method ◽  
Spinel Type ◽  
X Ray ◽  
Conventional Sintering ◽  
Lcr Meter ◽  
Citrate Precursor

Ni0.8-xCuxZn0.2Fe2O4 spinel type ferrite nanoparticles have been synthesized by citrate precursor method. These nanoparticles were then given heat treatment using microwave and conventional sintering techniques. Various characterizations using X-ray powder diffraction (XRD), scanning electron microscope (SEM), LCR meter, and B-H loop tracer were carried out on the sintered specimens. The XRD spectra of these ferrites confirmed the formation of spinel structure. The average crystallite size calculated using Scherrer’s formula was found to be in the nanometer range, its value varying from 33 nm to 39 nm. Microwave sintered samples exhibited superior electrical and magnetic behaviour over their conventionally sintered counterparts. Feasibility of low temperature synthesis and promising properties will render these ferrites suitable for multilayer chip inductor applications.

Sign in / Sign up

Export Citation Format

Share Document