Synthesis of a New Red Long Persistent Phosphor Sr2ZnSi2O7: Eu3+, Lu3+ via Sol–Gel Method and Investigation of its Luminescence

2011 ◽  
Vol 393-395 ◽  
pp. 362-365
Author(s):  
Hua Lin ◽  
A Xiao Xu ◽  
Guo Liang Chen ◽  
Zi Shan Zheng ◽  
Heng Lin ◽  
...  
Keyword(s):  
Uv Light ◽  
Sol Gel ◽  
Trap Depth ◽  
X Ray Diffraction ◽  
Red Phosphor ◽  
Gel Method ◽  
Sol Gel Method ◽  
Long Afterglow ◽  
Uv Light Irradiation ◽  
Luminescent Centers

A novel red long persistent phosphor of Sr2ZnSi2O7: Eu3+, Lu3+ was successfully synthesized with sol–gel method. Its properties were systematically characterized by X-ray diffraction(XRD), luminescence, afterglow decay curves and thermoluminescence (TL) spectra. The red phosphor showed one emission peak at 616.9nm, which is attributed to the typical 5D0–7F2 transition of Eu3+ ions as luminescent centers in Sr2ZnSi2O7 host. Lu3+ as a sensitized ion played an important role in enhancing the long afterglow performance of Sr2ZnSi2O7: Eu3+, Lu3+. Under UV light irradiation, this phosphor showed obvious red long-lasting phosphorescence that can be clearly seen with naked eyes in a dark room for over 20s after the irradiation source has been removed. Thermoluminescence (TL) measurement showed that Lu3+ co-dopan can reduce the trap depth of the title phosphor to obtain suitable ones.

N-Doped Cu11O2 (VO4)6 Photocatalyst Prepared by Sol-Gel Method

2011 ◽  
Vol 393-395 ◽  
pp. 1287-1290
Author(s):  
Min Wang ◽  
Qiong Liu ◽  
Qi Xing
Keyword(s):  
Uv Light ◽  
Sol Gel ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Photodegradation Rate ◽  
Triclinic Phase ◽  
Synthesized Materials

The N-doped Cu11O2 (VO4)6 photocatalyst was prepared using the sol-gel method. Techniques of X-ray diffraction (XRD), scanning electron microscope (SEM) have been employed to characterize the as-synthesized materials. During liquid phase photocatalytic degradation of Methy lorange(MO) under the UV-light, the as-prepared N-doped Cu11O2 (VO4)6 exhibits higher activity than the pure Cu11O2 (VO4)6 without doped N. It found that the N-doped Cu11O2 (VO4)6 prepared with the molar ratio of citric acid to metal inons be 2:1, N/Cu molar ratio of 12%, pH=7 and calcinated under 500°C for 4 hours was pure triclinic phase. In this conditions, the sample had highest photocatalytic activity with the photodegradation rate was about 94.42% or so in 60min under 20W ultraviolet lamp.

Effect of the Ce-Doped TiO2 on the Photocatalysis Degradation of MB

2013 ◽  
Vol 320 ◽  
pp. 220-225 ◽  
Author(s):  
Xiao Ye Fu ◽  
Xiu Hong Liang
Keyword(s):  
Visible Light ◽  
Uv Light ◽  
Sol Gel ◽  
Crystal Form ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Crystal Transformation ◽  
Infrared Spectrometer

In this paper, we prepared a series of powders (pure TiO2 and Ce-doped TiO2) by sol-gel method and characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), infrared spectrometer (IR) and UV spectrophotometer. The results indicated that the doped Ce influence the crystal structure of TiO2 and improve the temperature of crystal transformation. In the degradation of MB experiment, after 5 hours, the degradation efficiency of them (pure TiO2 , Ce-doped TiO2 and P25) under UV light is about 99.1%, while under visible light,Ce-doped TiO2 is about 60% higher than pure TiO2 and P25, up to 73%. This illustrates that the doped Ce increase the absorption to visible light and improve the photocatalytic efficiency.Key Words: TiO2, Ce-doped TiO2, photocatalyst, sol-gel method, crystal form

Preparation and Photocatalytic Preoperty of Cu11O2 (VO4)6 Photocatalyst by Sol-Gel Method

2011 ◽  
Vol 361-363 ◽  
pp. 1598-1601
Author(s):  
Min Wang ◽  
Qiong Liu ◽  
Hai Yan Luan
Keyword(s):  
Photocatalytic Activity ◽  
Citric Acid ◽  
Uv Light ◽  
Sol Gel ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Gel Method ◽  
Sol Gel Method ◽  
Photodegradation Rate ◽  
Synthesized Materials

Cu11O2 (VO4)6 powders have been synthesized by complexing Sol-Gel method using citric acid as chelate, calcined at different temperature without using any template. Techniques of X-ray diffraction (XRD) and scanning electron microscope (SEM) have been employed to characterize the as-synthesized materials. The photocatalytic activity was evaluated by photocatalytic degradation of methyl orange (MO) solution under UV-light. It revealed that temperature values can influence significantly on the morphologies and structures of the products.It also found that the sample prepared with the molar ratio of citric acid to metal inons be 2:1, pH=7 and calcinated under 500°C for 4 hours was pure triclinic Cu11O2 (VO4)6 phase.In this conditions, the sample had highest photocatalytic activity with the photodegradation rate was about 78.9% or so in 60min under 20W ultraviolet lamp.

Impedance Spectroscopy Study of LiTaO3 Powder Synthesized via Sol-Gel Method

2012 ◽  
Vol 545 ◽  
pp. 275-278 ◽  
Author(s):  
Lili Widarti Zainuddin ◽  
Norlida Kamarulzaman
Keyword(s):  
Room Temperature ◽  
Single Phase ◽  
Sol Gel ◽  
Rhombohedral Structure ◽  
Spectroscopy Study ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Impedance Spectroscopy Study

A ceramics sample of LiTaO3 was prepared using a sol-gel method. The sample is annealed at 750 °C for 48 hours. X-ray diffraction analysis indicate the formation of single phase, rhombohedral structure. An ac impedance study was used to analyse the conductivity of LiTaO3 at room temperature and at various temperatures.

Magnetic Properties of Bulk Zn0.95-XMnXFe0.05O2 Prepared by Sol-Gel Method and Subsequent Hot Pressing

2011 ◽  
Vol 268-270 ◽  
pp. 356-359 ◽  
Author(s):  
Wen Song Lin ◽  
C. H. Wen ◽  
Liang He
Keyword(s):  
Magnetic Properties ◽  
Photoelectron Spectroscopy ◽  
Raw Materials ◽  
Sol Gel ◽  
Secondary Phase ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Doped Zno

Mn, Fe doped ZnO powders (Zn0.95-xMnxFe0.05O2, x≤0.05) were synthesized by an ameliorated sol-gel method, using Zn(CH3COO)2, Mn(CH3COO)2and FeCl2as the raw materials, with the addition of vitamin C as a kind of chemical reducer. The resulting powder was subsequently compacted under pressure of 10 MPa at the temperature of 873K in vacuum. The crystal structure and magnetic properties of Zn0.95-xMnxFe0.05O2powder and bulk samples have been investigated by X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). X-ray photoelectron spectroscopy (XPS) was used to study chemical valence of manganese, iron and zinc in the samples. The x-ray diffraction (XRD) results showed that Zn0.95-xMnxFe0.05O (x≤0.05) samples were single phase with the ZnO-like wurtzite structure. No secondary phase was found in the XRD spectrum. X-ray photoelectron spectroscopy (XPS) showed that Fe and Mn existed in Zn0.95-xMnxFe0.05O2samples in Fe2+and Mn2+states. The results of VSM experiment proved the room temperature ferromagnetic properties (RTFP) of Mn, Fe co-doped ZnO samples.

Effect of replacement of Ca by Zn on the structure and optical property of CaTiO 3 :Eu 3+ red phosphor prepared by sol‐gel method

Luminescence ◽  
2014 ◽  
Vol 30 (5) ◽  
pp. 533-537 ◽  
Author(s):  
Yulong Wang ◽  
Wentao Zhang ◽  
Peicong Zhang ◽  
Junfeng Li ◽  
Jianping Long
Keyword(s):  
Optical Property ◽  
Sol Gel ◽  
Red Phosphor ◽  
Gel Method ◽  
Sol Gel Method

Fast response acetone-sensing properties of SnO2 nanoparticles prepared by the sol-gel method

2021 ◽  
Vol 93 (3) ◽  
pp. 30401
Author(s):  
Jiaxing Wang ◽  
Hai Yu ◽  
Yong Zhang
Keyword(s):  
High Performance ◽  
Gas Sensing ◽  
Sno2 Nanoparticles ◽  
Sol Gel ◽  
Fast Response ◽  
X Ray Diffraction ◽  
Gel Method ◽  
Sol Gel Method ◽  
Short Recovery Time ◽  
Acetone Gas Detection

SnO2 nanoparticle architectures were successfully synthesized using a sol-gel method and developed for acetone gas detection. The morphology and structure of the particles were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The SnO2 nanoparticle architectures were configured as high-performance sensors to detect acetone and showed a very fast response time (<1 s), a short recovery time (10 s), good repeatability and high selectivity at a relatively low working temperature. Thus, SnO2 nanoparticles should be promising candidates for designing and fabricating acetone gas sensors with good gas sensing performance. The possible gas sensing mechanism is also presented.

scholarly journals Effect of Preheating Temperature on Synthesis of Pure BiFeO3 via Sol–Gel Method

Nanopages ◽  
2019 ◽  
pp. 1-11
Author(s):  
G. M. Taha ◽  
M. N. Rashed ◽  
M. S. El-Sadek ◽  
M. A. Moghazy
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Pure Bifeo3 ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Transmission Electron ◽  
Preheating Temperature

Abstract BiFeO3 (BFO) nanopowder was synthesized in a pure form via a sol- gel method based on glycol gel reaction. Effect of drying and preheating temperature on preventing other phases was studied. Many parameters were studied as calcination temperature and time & stirring temperature as well. The prepared powder was characterized by X-Ray Diffraction of powder (XRD) and Transmission Electron Microscope (TEM). High pure BiFeO3 was obtained by preheated process at 400 °C for 0.5 h and calcination at 600 °C for 0.5 h without any impurities compared to dry at110 °C.

Effect of Synthesis Conditions on the Structure and Electrochemical Properties of LiNi1/2Mn1/2O2 by Sol Gel Method

2011 ◽  
Vol 399-401 ◽  
pp. 1447-1450
Author(s):  
Zhi Yong Yu ◽  
Han Xing Liu
Keyword(s):  
Electrochemical Properties ◽  
Sol Gel ◽  
Electrochemical Analysis ◽  
X Ray Diffraction ◽  
Capacity Fading ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Synthesis Conditions ◽  
A Current

The layered LiNi1/2Mn1/2O2 cathode materials were synthesized by a sol gel method. The effects of calcination temperature and time on the structural and electrochemical properties of the LiNi1/2Mn1/2O2 were investigated. The prepared samples were characterized by X-ray diffraction (XRD) and electrochemical analysis. The results revealed that the layered LiNi1/2Mn1/2O2 material could be optimal synthesized at temperature of 900°C for 10h. The sample prepared under the above conditions has the highest initial discharge capacity of 151 mAh/g and showed no dramatic capacity fading during 20 cycles between 2.5-4.5V at a current rate of 20mA/g.

scholarly journals Magnetic PbFe12O19-TiO2 nanocomposites and their photocatalytic performance in the removal of toxic pollutants

2018 ◽  
Vol 41 (3-4) ◽  
pp. 53-62 ◽  
Author(s):  
Behnaz Lahijani ◽  
Kambiz Hedayati ◽  
Mojtaba Goodarzi
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Performance ◽  
Sol Gel ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Gel Method ◽  
Sol Gel Method ◽  
Photocatalytic Effect ◽  
Transmission Electron ◽  
Ultraviolet Light Irradiation

Abstract In this work, the PbFe12O19 nanoparticles were prepared by the simple and optimized precipitation method with different organic surfactants and capping agents. In the next step, the TiO2 nanoparticles were synthesized using the sol-gel method. At the final step, the PbFe12O19-TiO2 nanocomposites were prepared via the sol-gel method. The effect of the precipitating agent on the morphology and particle size of the products was investigated. The prepared products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. The results obtained by the vibrating sample magnetometer show the magnetic properties of the ferrite nanostructures. The photocatalytic effect of the PbFe12O19-TiO2 nanocomposite on the elimination of the azo dyes (acid black, acid violet and acid blue) under ultraviolet light irradiation was evaluated. The results indicate that the prepared nanocomposites have acceptable magnetic and photocatalytic performance.

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