ChemInform Abstract: SEGREGATION OF LITHIUM OXIDE AT THE GRAIN BOUNDARIES OF ZINC OXIDE

1978 ◽  
Vol 9 (27) ◽  
Author(s):  
Y. MORIYOSHI ◽  
S. SHIRASAKI ◽  
E. S. LEE ◽  
K. TAKAHASHI ◽  
M. ISOBE ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Grain Boundaries ◽  
Lithium Oxide

Highly active zinc oxide-supported lithium oxide catalyst for solvent-free Knoevenagel condensation

2021 ◽  
Vol 133 (3) ◽  
Author(s):  
Prasad Sunkara ◽  
Keshavulu Masula ◽  
Veerasomaiah Puppala ◽  
Yadagiri Bhongiri ◽  
Vijay Kumar Pasala ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Oxide Catalyst ◽  
Knoevenagel Condensation ◽  
Solvent Free ◽  
Lithium Oxide ◽  
Highly Active

scholarly journals Electrical properties of mechanically activated zinc oxide

2006 ◽  
Vol 38 (2) ◽  
pp. 131-138 ◽  
Author(s):  
K. Vojisavljevic ◽  
M. Zunic ◽  
G. Brankovic ◽  
T. Sreckovic
Keyword(s):  
Zinc Oxide ◽  
Electrical Properties ◽  
Grain Boundaries ◽  
Arrhenius Equation ◽  
Electrical Response ◽  
High Energy ◽  
Microstructural Properties ◽  
Impedance Analyzer ◽  
Zinc Oxide Powder ◽  
Zno Ceramics

Microstructural properties of a commercial zinc oxide powder were modified by mechanical activation in a high-energy vibro-mill. The obtained powders were dry pressed and sintered at 1100?C for 2 h. The electrical properties of grain boundaries of obtained ZnO ceramics were studied using an ac impedance analyzer. For that purpose, the ac electrical response was measured in the temperature range from 23 to 240?C in order to determine the resistance and capacitance of grain boundaries. The activation energies of conduction were obtained using an Arrhenius equation. Donor densities were calculated from Mott-Schottky measurements. The influence of microstructure, types and concentrations of defects on electrical properties was discussed.

scholarly journals Effect of Zinc Oxide on the Efficiency Enhancement of Al/Li2O/PSi/Si/Al solar cell

2021 ◽  
Author(s):  
Shahlaa M. Abd Al-Hussan ◽  
Nabeel A. Bakr ◽  
Ahmed N. Abd
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Zinc Oxide ◽  
Porous Silicon ◽  
Lithium Oxide ◽  
Precipitation Method ◽  
Oxide Nanoparticles ◽  
Casting Method ◽  
P Type ◽  
Scanning Electron

Abstract In this paper, electrochemical etching of the p-type silicon wafer is used to prepare p-type porous silicon with current density of 10 mA.cm− 2 for 10 minutes. Field Emission Scanning Electron Microscopy (FESEM) has been used to study porous silicon layer surface morphology. Zinc oxide and lithium oxide nanoparticles are prepared separately by chemical precipitation method and simple precipitation method, respectively and deposited on glass substrates by drop casting method. Moreover,, the structural properties of the films were analyzed by using XRD and SEM. The XRD results showed that the ZnO and Li2O films are polycrystalline with hexagonal wurtzite structure and cubic structure, and preferred orientation along (101) and (003) planes, respectively. Using Scherrer's formula, the crystallite size was measured and it was found that ZnO and Li2O thin films have a crystallite size of 22.04 and 45.6 nm respectively. Surface topography of the prepared thin films is studied by using Scanning Electron Microscopy (SEM). Later, certain proportions of both materials were mixed and deposited on porous silicon using drop casting method at thickness of 1.4 µm. After that, the characteristics of the solar cell were investigated. Mixing zinc oxide nanoparticles in particular proportions with lithium oxide played a major role in increasing the solar cell's performance. The highest prepared film efficiency was obtained at mixing ratio (0.5: 0.5) for (ZnO: Li2O) and its value was (11.09 %).

Continuous Existence of Bismuth at Grain Boundaries of Zinc Oxide Varistor without Intergranular Phase

2005 ◽  
Vol 81 (8) ◽  
pp. 2071-2076 ◽  
Author(s):  
Kei-Ichiro Kobayashi ◽  
Osamu Wada ◽  
Masahiro Kobayashi ◽  
Yoshio Takada
Keyword(s):  
Zinc Oxide ◽  
Grain Boundaries ◽  
Intergranular Phase ◽  
Zinc Oxide Varistor

High Barrier Effects of (0001)|(0001) Zinc Oxide Bicrystals: Implication for Varistor Ceramics with Inversion Boundaries

2005 ◽  
Vol 20 (8) ◽  
pp. 2101-2109 ◽  
Author(s):  
Jong-Sook Lee ◽  
Joachim Maier
Keyword(s):  
Zinc Oxide ◽  
Grain Boundaries ◽  
Grain Growth ◽  
Growth Behavior ◽  
Impurity Effects ◽  
Barrier Effects ◽  
Zno Varistor ◽  
Grain Growth Behavior ◽  
Superior Property ◽  
Strong Barrier

Inversion boundaries (IBs) of a head-to-head or (0001)|(0001) (C+|C+) configuration bisect virtually every grain in typical commercial ZnO varistor ceramics. They are most often considered electrically inactive, and the effect on the grain growth behavior has been recently addressed. In this work, various configurations of ZnO bicrystals were prepared using different source crystals and strong barrier effects were observed in some (0001)|(0001) (C−|C−) bicrystals using crystals with higher impurity contents. The crystallographic polarity and impurity effects were systematically examined by doping C+|C+ and C−|C− bicrystals with single and double additives of Mn, Co, Ni, and Bi. Varying degrees of barrier effects including varistor-like behaviors were observed in C−|C− bicrystals depending on dopants, while C+|C+ bicrystals consistently exhibited negligible effects. Because the IBs in ZnO varistor ceramics preferentially expose C− surfaces in the grain boundaries, the superior property of commercial ZnO varistor ceramics is suggested to be assisted by the presence of IBs.

Grain Boundary Dopant and Heat Treatment Effects on the Electrical Properties of Polycrystalline ZnO

1995 ◽  
Vol 411 ◽  
Author(s):  
T. D. Chen ◽  
J.-R. Lee ◽  
H. L. Tuller ◽  
Y.-M. Chiang
Keyword(s):  
Heat Treatment ◽  
Zinc Oxide ◽  
Electrical Properties ◽  
Grain Boundary ◽  
Grain Boundaries ◽  
Deep Level Transient Spectroscopy ◽  
Deep Level ◽  
Low Leakage ◽  
Current Voltage ◽  
Transient Spectroscopy

ABSTRACTSimplified varistor systems of bismuth- and cobalt-doped zinc oxide are studied. A prior study has shown that the distributions of bismuth segregation at the grain boundaries in such samples can be controlled by varying microstructure and heat treatment. Current-voltage and deep level transient spectroscopy measurements were done to evaluate the corresponding electrical properties. Low leakage and α values of ˜30 were attained, despite the nominal, twocomponent doping of these simplified varistors. Moreover, these samples show the signature defects that are found in many multi-dopant, commercial devices: two shallow bulk traps at ˜0.14 eV and ˜0.24 eV and one prominent interfacial trap at ˜1 eV.

Complex plane analysis of trapping phenomena in zinc oxide based varistor grain boundaries

1988 ◽  
Vol 63 (7) ◽  
pp. 2337-2345 ◽  
Author(s):  
Mohammad A. Alim ◽  
Martin A. Seitz ◽  
Richard W. Hirthe
Keyword(s):  
Zinc Oxide ◽  
Grain Boundaries ◽  
Complex Plane ◽  
Plane Analysis
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