Dopant effects on the structural, low temperature Raman scattering and electrical transport properties in SrTi1−x FexO3 nanoparticles synthesized by sol-gel method

2010 ◽  
Vol 55 (2) ◽  
pp. 255-260 ◽  
Author(s):  
Nguyen Van Minh ◽  
Doan Thi Thuy Phuong
Keyword(s):  
Low Temperature ◽  
Raman Scattering ◽  
Transport Properties ◽  
Electrical Transport ◽  
Sol Gel ◽  
Electrical Transport Properties ◽  
Gel Method ◽  
Sol Gel Method

scholarly journals Magnetic and Electrical Transport Properties of Double Perovskite Sr2FeMoO6Prepared by Sol-Gel Method

2011 ◽  
Vol 8 (s1) ◽  
pp. S189-S194 ◽  
Author(s):  
Yong-Qing Zhai ◽  
Jing Qiao ◽  
Zhang Zhang
Keyword(s):  
Transport Properties ◽  
Electrical Transport ◽  
Room Temperature ◽  
Sol Gel ◽  
Double Perovskite ◽  
Reducing Agent ◽  
Perovskite Oxide ◽  
Electrical Transport Properties ◽  
Gel Method ◽  
Sol Gel Method

With activated carbon for reducing agent, the sol-gel method was used to prepare the giant magnetoresistance materials Sr2FeMoO6, which is the double Perovskite oxide. The structure, morphology, magnetic and electrical transport properties were investigated respectively by x-ray diffraction, scanning electron microscopy and vibrating sample magnetometer. The as-synthesized sample is Sr2FeMoO6with tetragonal crystal structure and I4/mmm space group and unit cell parameter is a = 5.580Å, c = 7.882Å. The primary particles are spherical in shape and the grain size is below 100 nm. The curie temperature is above room temperature and the saturation magnetization is 13.321 A·m2/kg under 1.0 T at room temperature. The sample exhibit typical semiconductor behavior and the conductive mechanism can be described by small polaron variable range hopping model. The room temperature magnetoresistance of the sample under 1.0 T field is up to -10.02%. Moreover, it is found the dosage of citric acid and the amount of reducing agent has great effect on the phase structure and magnetic properties of the samples.

DOPANT EFFECTS ON THE STRUCTURAL, OPTICAL AND ELECTRICAL TRANSPORT PROPERTIES IN SrTi1-xCoxO3 NANOPARTICLES SYNTHESIZED BY SOL–GEL METHOD

2010 ◽  
Vol 19 (02) ◽  
pp. 219-227
Author(s):  
DOAN THI THUY PHUONG ◽  
NGUYEN VAN MINH
Keyword(s):  
Transport Properties ◽  
Electrical Transport ◽  
Annealing Temperature ◽  
Dopant Concentration ◽  
Sol Gel ◽  
Average Particle Size ◽  
Average Particle ◽  
Electrical Transport Properties ◽  
Gel Method ◽  
Sol Gel Method

We investigate effects of Co dopant concentration on the structure, as well as optical and electrical transport properties in SrTi 1-x Co x O 3 (x = 0.00, 0.10, 0.20, 0.30, 0.40, 0.50) nanoparticles prepared by sol–gel method with annealing temperature considerably lower than that employed conventionally. The dopant-induced changes are studied by XRD, Raman, Optical absorption and Impedance measurements. The results show an average particle size of about 30 nm, and decreasing lattice parameters. In the Raman spectra, a broad structure in the region 200–500 cm-1 is almost absent and the peaks in the region 600–800 cm-1 show different relative weights with respect to those from SrTiO 3, which is related to structural changes, decreasing gap with increasing dopant concentration in conjuction with increasing grain boundary contribution to the impedance. These results also demonstrate the feasibility of synthesizing the compound with low annealing temperature.

Synthesis of Aluminum Titanate Powder at Low Temperature via Nonhydrolytic Sol-Gel Method by Using Aluminum Powder

2013 ◽  
Vol 745-746 ◽  
pp. 673-678 ◽  
Author(s):  
Wei Hui Jiang ◽  
Zhi Fang Xu ◽  
Jian Min Liu ◽  
Qing Xia Zhu ◽  
Quan Zhang
Keyword(s):  
Low Temperature ◽  
Aluminum Powder ◽  
Raw Materials ◽  
Sol Gel ◽  
Aluminum Titanate ◽  
Gel Method ◽  
Sol Gel Method ◽  
Transmission Electron ◽  
Oxygen Donor ◽  
Metal Aluminum

Aluminum titanate (Al2TiO5) powder has been synthesized at low temperature via nonhydrolytic sol-gel method by using aluminum powder as aluminum source, titanium tetrachloride as titanium source, anhydrous ethanol as oxygen donor with different catalysts. The phase transformation of aluminum titanate xerogel powder during heat treatment and the influence of the mixing orders of raw materials, catalyst kinds on the synthesis of aluminum titanate were investigated by means of differential-thermal analysis (DTA-TG), X-ray diffraction (XRD), transmission electron microscope (TEM). The results indicated that aluminum titanate powder was easily synthesized at 750 °C by using AlCl3 as catalyst with a mixing order of adding TiCl4 before AlCl3 into aluminum alcohol mixture. The catalytic order of the different catalysts in the preparation process of aluminum titanate is: FeCl3> AlCl3> MgCl2. The catalyst promoted the activation of metal aluminum powder and played a major role in the synthesis of aluminum titanate powder at low temperature via nonhydrolytic sol-gel method.

Effect of Sintering on Structural and Transport Properties on Nanosized Pr0.85Na0.15MnO3

2015 ◽  
Vol 1107 ◽  
pp. 272-277 ◽  
Author(s):  
Siau Wei Ng ◽  
Kean Pah Lim ◽  
S.A. Halim ◽  
Hassan Jumiah ◽  
Albert H.M. Gan ◽  
...  
Keyword(s):  
Grain Size ◽  
Transport Properties ◽  
Electrical Transport ◽  
Boundary Effect ◽  
Sol Gel ◽  
Magnetic Layer ◽  
Electrical Transport Properties ◽  
Orthorhombic Crystal ◽  
Orthorhombic Crystal Structure ◽  
Semiconductor Behavior

We have investigated the structural, microstructure and electrical transport properties of nanosized Pr0.85Na0.15MnO3 (PNMO) synthesized by sol-gel technique and sinter from 600°C to 1000°C. The grain size increases from 67 nm (S600) up to 284 nm (S1000) due to the grain growth during heat treatment. XRD showed that single phase orthorhombic crystal structure of PNMO is fully forms started at 600°C. The resistivity decreased with the increased of grain size and crystallite size due to the reduction of grain boundary effect (dead magnetic layer) which improved their grain conductivity.All samples showed semiconductor behavior where their metal insulator transition temperatures (TMIT) were estimated to be lower than 80K.

Sign in / Sign up

Export Citation Format

Share Document