NiO Sensing Electrode for NOx Detection at High Temperature

2013 ◽  
Vol 544 ◽  
pp. 76-80
Author(s):  
Tao Feng ◽  
Jin Feng Xia ◽  
Hong Qiang Nian ◽  
De Xin Huang ◽  
Hai Fang Xu ◽  
...  
Keyword(s):  
Screen Printing ◽  
Complex Impedance ◽  
Yttria Stabilized Zirconia ◽  
Impedance Spectra ◽  
X Ray Diffraction ◽  
Stabilized Zirconia ◽  
X Ray ◽  
Screen Printing Technique ◽  
Printing Technique ◽  
Complex Impedance Spectra

Mixed-potential-type NO2 sensor based on yttria-stabilized zirconia(YSZ) with NiO sensing electrode was prepared by the screen-printing technique and its physical characteristics were studied by the X-ray diffraction and scanning electron microscope. The response of electromotive force (EMF) and complex impedance of the sensor were tested under different NO2 concentrations and temperatures. The results show that, at the range of 550–750 °C, the EMF values are negative and almost linear to the logarithm of NO2 concentration. But the sensitivity of the sensor and the amplitude of the EMF response to NO2 concentration both obviously decrease with the increase of the work temperature. In addition, the semicircular arcs of the complex impedance spectra shrink regularly with a raise of NO2 concentration at 600 °C.

A Simple Model for Predicating Dielectric Constant of CaCu3Ti4O12-SrTiO3 Composite Ceramics

2011 ◽  
Vol 689 ◽  
pp. 24-28
Author(s):  
Hong Tao Yu ◽  
Wen Bo Zhang ◽  
Jing Song Liu ◽  
Lin Hong Cao ◽  
Han Xing Liu
Keyword(s):  
Dielectric Constant ◽  
Simple Model ◽  
Complex Impedance ◽  
Impedance Spectra ◽  
Composite Ceramics ◽  
X Ray Diffraction ◽  
X Ray ◽  
Grain Sizes ◽  
Complex Impedance Spectra ◽  
Variation Tendency

In this work, we have proposed a simple model to predicte the dielectric constant of CaCu3Ti4O12-SrTiO3composite ceramics. The model has been established based on the analysis of composition and microstructure. Two different compositions in the composite ceramics correspond to two different grain sizes, large for CaCu3Ti4O12, and small for SrTiO3, which has been identified by the x-ray diffraction, the scanning electron microscope and the energy spectrum analysis. All specimens have been assumed to be the barrier layer dielectrics in the model, according to the complex impedance spectra. The dielectric constant of serial, parallel, and logarithmic mixture models has been discussed. Compared with the experimental results, the model shows the similar variation tendency as SrTiO3content increases.

Humidity Sensing Property of Al-Doped Mesoporous Silica

2012 ◽  
Vol 249-250 ◽  
pp. 992-997 ◽  
Author(s):  
Wang Chang Geng ◽  
Li Bing Duan ◽  
Qiu Yu Zhang
Keyword(s):  
Relative Humidity ◽  
Mesoporous Silica ◽  
Complex Impedance ◽  
Impedance Spectra ◽  
X Ray Diffraction ◽  
Humidity Sensing ◽  
X Ray ◽  
Sensing Mechanism ◽  
Sensing Material ◽  
Complex Impedance Spectra

In order to study the humidity sensing property and sensing mechanism of Al-doped mesoporous silica SBA-15 (Al-SBA-15), Al-SBA-15 was prepared by a simple grind method following a heat-treatment process. Its structure and morphology was characterized by X-ray diffraction (XRD), Infrared (IR), scanning electron microscope (SEM). Humidity sensing response was studied and the results indicated that Al-SBA-15 displayed better sensing property when the frequency was 100 Hz. The impedance of Al-SBA-15 changes three orders of magnitude when relative humidity changes from 11% to 95%. Complex impedance spectra, the corresponding equivalent circuit under different relative humidity are carefully analyzed to explore the humidity sensing mechanism of this material. This material can be used as a promising humidity sensing material.

Fabrication of (Cu,Ag)InSe2 Thin films by a Combination of Mechanochemical and Screen Printing/Sintering Processes

2007 ◽  
Vol 1012 ◽  
Author(s):  
Syuusuke Nomura ◽  
Yoshihiro Matsuo ◽  
Takahiro Wada
Keyword(s):  
Solid Solution ◽  
Atmospheric Pressure ◽  
Screen Printing ◽  
Fine Powder ◽  
X Ray Diffraction ◽  
X Ray ◽  
Screen Printing Technique ◽  
Printing Technique ◽  
Precursor Layer ◽  
Sintering Processes

AbstractWe successfully prepared (Cu1-XAgx)InSe2 solid solution with 0 ¡Ü x ¡Ü 1.0 by a mechanochemical process without any additional heating. The obtained fine powder was suitable for screen-printing. Particulate precursors were deposited in a thin layer by a screen-printing technique and then the porous precursor layer was sintered into a dense polycrystalline film by atmospheric-pressure firing. The crystal structures of the powder and the film were analyzed by x-ray diffraction and the microstructure of the film was observed in an SEM. For the (Cu1-XAgx)InSe2 films with x ¡Ü 0.2, the (Cu,Ag)InSe2 films had a good microstructure for the solar cell absorbers.

Characterizations of Synthetic 8mol% YSZ with Comparison to 3mol %YSZ for HT-SOFC

2020 ◽  
Vol 38 (4A) ◽  
pp. 491-500
Author(s):  
Abeer F. Al-Attar ◽  
Saad B. H. Farid ◽  
Fadhil A. Hashim
Keyword(s):  
Ionic Conductivity ◽  
Electrochemical Impedance ◽  
Structural Information ◽  
Impedance Analysis ◽  
High Energy ◽  
Yttria Stabilized Zirconia ◽  
X Ray Diffraction ◽  
Stabilized Zirconia ◽  
Powder Morphology ◽  
X Ray

In this work, Yttria (Y2O3) was successfully doped into tetragonal 3mol% yttria stabilized Zirconia (3YSZ) by high energy-mechanical milling to synthesize 8mol% yttria stabilized Zirconia (8YSZ) used as an electrolyte for high temperature solid oxide fuel cells (HT-SOFC). This work aims to evaluate the densification and ionic conductivity of the sintered electrolytes at 1650°C. The bulk density was measured according to ASTM C373-17. The powder morphology and the microstructure of the sintered electrolytes were analyzed via Field Emission Scanning Electron Microscopy (FESEM). The chemical analysis was obtained with Energy-dispersive X-ray spectroscopy (EDS). Also, X-ray diffraction (XRD) was used to obtain structural information of the starting materials and the sintered electrolytes. The ionic conductivity was obtained through electrochemical impedance spectroscopy (EIS) in the air as a function of temperatures at a frequency range of 100(mHz)-100(kHz). It is found that the 3YSZ has a higher density than the 8YSZ. The impedance analysis showed that the ionic conductivity of the prepared 8YSZ at 800°C is0.906 (S.cm) and it was 0.214(S.cm) of the 3YSZ. Besides, 8YSZ has a lower activation energy 0.774(eV) than that of the 3YSZ 0.901(eV). Thus, the prepared 8YSZ can be nominated as an electrolyte for the HT-SOFC.

Effect of Yttria-Stabilized Zirconia Concentration in an Electroless Bath on Microstructure and Composition of Ni/Yttria-Stabilized Zirconia Nanocomposite

2021 ◽  
Vol 21 (11) ◽  
pp. 5592-5602
Author(s):  
Samira Almasi ◽  
Ali Mohammad Rashidi
Keyword(s):  
High Performance ◽  
Yttria Stabilized Zirconia ◽  
X Ray Diffraction ◽  
Stabilized Zirconia ◽  
Nickel Ion ◽  
Nanocomposite Particles ◽  
X Ray ◽  
Ni Content ◽  
Naoh Solution ◽  
Average Size

The effect of the yttria-stabilized zirconia (YSZ) nanoparticle loading in an electro-less bath was considered as one of the vital synthesis variables for control Ni content and microstructure of prepared nanocomposite particles, which are two crucial factors to achieving high-performance SOFC anode. Nanocomposite particles were prepared using a simple electroless method without any expensive pretreatment of sensitizing by Sn2+ ions as well as activating by Pd2+ ions that are usually used to apply nickel coating on the surface of a non-conductive substrate. The process was performed by adding YSZ nanoparticles into NaOH solution, separating them from the solution by the centrifugal method, then providing several water-based nanofluids with different concentrations of activated YSZ nanoparticles, mixing them with NiCI2 solution, followed by adding the hydrazine and then NaOH solution. X-ray diffraction and scanning electron microscopy coupled with energy dispersive X-ray analysis were used to analyze the prepared nanocomposite particles. It is observed that after adding YSZ nanoparticles into the NaOH solution, the pH of the solution varied gradually from a starting pH of 10.2 to 9. Also, by increasing the YSZ nanoparticles loading in the electroless bath from 76 mg/l to 126 mg/l, the grain size of Ni deposits, the Ni content and the average size of the prepared nanocomposite particles decreased. The electrochemical mechanism previously proposed for the nickel ion reduction was modified, and a novel analytical model was proposed for variation of the efficiency of Ni deposition with YSZ nanoparticles loading.

scholarly journals Textiles Printing Using Microencapsulated Pigments in Biodegradable Thickeners

2018 ◽  
Vol 15 (1) ◽  
pp. 6122-6129 ◽  
Author(s):  
Meram S. Abdelrahman ◽  
Sahar Nassar ◽  
Hamada Mashaly ◽  
Safia Mahmoud ◽  
Dalia Maamoun
Keyword(s):  
Screen Printing ◽  
Average Particle Size ◽  
Morphological Structure ◽  
Core Material ◽  
Average Particle ◽  
X Ray ◽  
Screen Printing Technique ◽  
Printing Technique ◽  
Encapsulation Process ◽  
Dispersing Agents

Micro-encapsulated pigments were formulated into biodegradable printing pastes and their properties were analyzed. The pigment was used as the core material and polylactic-based biodegradable thickener was used as the wall-former. Cotton/polyester blend fabric was printed with micro-encapsulated pigment using screen-printing technique without dispersing agents, penetrating agents, leveling agents or other auxiliaries. Micro-encapsulated pigment has been characterized in terms of average particle size and size distribution, morphological structure and elemental composition using scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The variations in viscosity and paste stability were observed upon storing over 7 days at ambient temperature. For permanence, the micro-encapsulation process afforded better colorfastness properties against light, washing, rubbing, and perspiration.

EPITAXIAL GROWTH OF YTTRIA-STABILIZED ZIRCONIA FILMS ON SILICON BY R.F. MAGNETRON SPUTTERING

1991 ◽  
Vol 05 (27) ◽  
pp. 1829-1835 ◽  
Author(s):  
Q.X. SU ◽  
L. LI ◽  
Y.Y. ZHAO ◽  
Y.Z. ZHANG ◽  
P. XU
Keyword(s):  
Magnetron Sputtering ◽  
Yttria Stabilized Zirconia ◽  
Processing Conditions ◽  
Full Width ◽  
X Ray Diffraction ◽  
Stabilized Zirconia ◽  
X Ray ◽  
Si Substrates ◽  
Zirconia Films ◽  
Scanning Electron

Yttria-stabilized Zirconia(YSZ) films were deposited on (100)Si substrates by R.F. magnetron sputtering method. X-ray diffraction analysis showed that the best YSZ films were cubic in structure and was grown epitaxially with (100) orientation. The (200) peak of YSZ films was 0.8° of the full width at half of the maximum, X-ray diffraction based on Seemann-Bohlin focusing geometry showed no peaks. The morphology of the YSZ films was observed by scanning electron microscopy. The effects of the processing conditions (such as substrate temperature, oxygen partial pressure, etc.) on the structure of the film were also discussed.

Synchrotron radiation study of yttria-stabilized zirconia, Zr0.758Y0.242O1.879

1999 ◽  
Vol 55 (5) ◽  
pp. 726-735 ◽  
Author(s):  
N. Ishizawa ◽  
Y. Matsushima ◽  
M. Hayashi ◽  
M. Ueki
Keyword(s):  
Synchrotron Radiation ◽  
Single Crystal ◽  
Yttria Stabilized Zirconia ◽  
Data Sets ◽  
X Ray Diffraction ◽  
Stabilized Zirconia ◽  
X Ray ◽  
Ideal Position ◽  
Fluorite Type ◽  
The Ideal

The fluorite-related cubic structure of yttria-stabilized zirconia, Zr0.75 8Y0.24 2O1.87 9, has been studied by single-crystal X-ray diffraction using synchrotron radiation and by EXAFS. Two diffraction data sets obtained at X-ray energies of 512 and 10 eV below the Y K edge revealed that in the average structure Zr atoms are displaced from the origin of the space group Fm3¯m along 〈111〉 by 0.19 Å, while Y atoms reside at the origin. Approximately 48% of the O atoms occupy the ideal position in the fluorite-type structure, while 43% of O atoms are displaced from the ideal position along 〈001〉 by 0.31 Å. The remaining 9% of O atoms are presumably sited at interstitial positions. Local structures around Zr and Y are investigated by combining the results of single-crystal X-ray diffraction and EXAFS studies.

Fabrication of Porous YSZ from ZnO-YSZ Cermet

2007 ◽  
Vol 124-126 ◽  
pp. 235-238
Author(s):  
Moon Jin Hwang ◽  
Chong Soo Han
Keyword(s):  
Electron Microscope ◽  
Gas Permeability ◽  
Acid Leaching ◽  
Yttria Stabilized Zirconia ◽  
X Ray Diffraction ◽  
Stabilized Zirconia ◽  
Scanning Electron Microscope Image ◽  
X Ray ◽  
Electron Microscope Image ◽  
Scanning Electron

Porous YSZ(8 mol% yttria-stabilized zirconia) was prepared by an acid leaching of ZnO-YSZ composite. The ZnO-YSZ composites were obtained by two different methods, a 1450 °C sintering of the mechanical mixture of ZnO and YSZ powders or a decomposition of Zn(NO3)2 deposited on YSZ and a subsequent sintering. The XRD (X-ray diffraction) pattern of the composite indicated that it was a mixture of ZnO and YSZ even after the sintering. Sharp edge or round edge of YSZ was observed in SEM (Scanning Electron Microscope) image of the porous-YSZ from the mixture of ZnO and YSZ, or Zn(NO3)2 deposited on YSZ, respectively. The porous YSZ from the composite having ZnO component greater than 60 wt% shows low mechanical strength. As the ZnO content of the composite increased, the porosity and gas permeability of the porous YSZ increased. From the result, it was suggested that ZnO is a candidate to generate pores in YSZ bulk or membrane.

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