Electrical Conductivity of Quantum Size 2d Nanocomplex

2005 ◽  
Vol 23 ◽  
pp. 335-338 ◽  
Author(s):  
N. Gupta ◽  
H. Mallik ◽  
A. Sarkar
Keyword(s):  
Size Effect ◽  
Self Assembly ◽  
Energy Levels ◽  
Sol Gel ◽  
Quantum Size Effect ◽  
X Ray Diffraction ◽  
Distinctive Features ◽  
Quantum Size ◽  
Transmission Electron ◽  
Base Matrix

A nanocomplex of Chromium oxide nanoparticles with biopolymer matrix of gum Arabica is synthesized by natural self-assembly in chemical sol-gel route. Gum Arabica is chosen as base matrix due to its inherent biodegradable property. Experimental specimen of the said complex is prepared to satisfy near quantum size effect criterion. Due to near quantum size effect and spatial localization of nanoclusters, the developed specimen becomes an ideal 2D quantum well system. The longitudinal electrical conduction of the developed system is studied experimentally. Some of its structural aspects are also investigated to make the study conclusive. The dispersed cluster size is estimated by Transmission Electron Microscope (TEM) and X-ray diffraction (XRD). The results of I-V characteristics at temperatures 253 K show the distinctive features of localized energy levels. The spacing between energy levels near ground state to be comparable to the thermal energy at temperature 253 K for a cluster dimension below 10 nm. In this present study the developed specimens with the mentioned nanoclusters estimated from TEM and XRD as below 10 nm. The overall results are found to be encouraging.

scholarly journals Interface between Quantum-Size-Effect Pb Nanocrystals and the Si(111)7 × 7 Substrate: an X-Ray Diffraction Study

2009 ◽  
Vol 41 (5) ◽  
pp. 1159-1161 ◽  
Author(s):  
M. W. Gramlich ◽  
S. T. Hayden ◽  
C. A. Jeffrey ◽  
C. Kim ◽  
R. Feng ◽  
...  
Keyword(s):  
Size Effect ◽  
Diffraction Study ◽  
Quantum Size Effect ◽  
X Ray Diffraction ◽  
X Ray ◽  
Quantum Size

Synthesis and Characterization of Mesoporous Silica Nanoparticles Embedded Gadolinium Oxide

2011 ◽  
Vol 306-307 ◽  
pp. 1275-1279 ◽  
Author(s):  
Ning Qi Luo ◽  
Zhan Yun Huang ◽  
Ping Luo ◽  
Yuan Zhi Shao ◽  
Di Hu Chen
Keyword(s):  
Mesoporous Silica ◽  
Self Assembly ◽  
Mesoporous Silica Nanoparticles ◽  
Sol Gel ◽  
Mesoporous Structure ◽  
Gadolinium Oxide ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
The Mean

We first synthesized gadolinium oxide (Gd2O3) by a modified “polyol” strategy and then embedded it into mesoporous silica by a simple self-assembly sol-gel reaction. Scanning electron microscope (SEM) results show that the samples have good sphericity and good dispersibility. The structure of mesoporous silica was characterized by transmission electron microscopy (TEM) and small-angle X-ray diffraction (SAXRD). Results show that the mesoporous structure has not been destroyed after gadolinium oxide imbedding. The ratio of gadolinium and silica was determined by the mean of energy dispersive spectroscopy (EDS).

One-pot synthesis of CdSe nanoparticles exhibiting quantum size effect within a sol–gel derived ureasilicate matrix

2014 ◽  
Vol 285 ◽  
pp. 21-29 ◽  
Author(s):  
Luis F.F.F. Gonçalves ◽  
Fehmida K. Kanodarwala ◽  
John A. Stride ◽  
Carlos J.R. Silva ◽  
Mario R. Pereira ◽  
...  
Keyword(s):  
Size Effect ◽  
Sol Gel ◽  
Quantum Size Effect ◽  
Cdse Nanoparticles ◽  
One Pot ◽  
One Pot Synthesis ◽  
Quantum Size

One-pot synthesis of CdS nanoparticles exhibiting quantum size effect prepared within a sol–gel derived ureasilicate matrix

2013 ◽  
Vol 36 (2) ◽  
pp. 186-190 ◽  
Author(s):  
Luis F.F.F. Gonçalves ◽  
Fehmida K. Kanodarwala ◽  
John A. Stride ◽  
Carlos J.R. Silva ◽  
Maria J.M. Gomes
Keyword(s):  
Size Effect ◽  
Sol Gel ◽  
Quantum Size Effect ◽  
Cds Nanoparticles ◽  
One Pot ◽  
One Pot Synthesis ◽  
Quantum Size

Quantum Size Effect in Polysilicon Gates

1987 ◽  
Vol 106 ◽  
Author(s):  
N. Lifshitz ◽  
S. Laryi ◽  
T. T. Sheng
Keyword(s):  
Size Effect ◽  
Columnar Structure ◽  
Quantum Size Effect ◽  
Oxide Semiconductor ◽  
Quantum Size ◽  
Transmission Electron ◽  
High Temperature Anneal ◽  
Low Energies ◽  
Work Functions ◽  
Work Function Difference

ABSTRACTIt has been observed by several authors that metal-oxide-semiconductor devices with polycrystalline Si (polySi) gates behave differently depending on the doping species in polySi: the work-function difference between the silicon substrate and the gate (øps) is higher when the gates are doped with arsenic than when they are doped with phosphorus.We believe that the different behavior of øps. can be explained by different grain textures at the polySi/SiO2 interface. Our transmission electron microscoey of the films indicates that while P-doped material consists of large (≈3000Å) grains, As-doped polySi preserves its as-deposited columnar structure – even after a high temperature anneal. Moreover, at the interface with the gate oxide an as-deposited microstructure with very small (≈100Å) “embrionic” grains is preserved. On the basis of these observations, we suggest a model for the different behavior of ø ps. The model is based on a quantum-size effect which becomes important for such small grain dimensions at the interface in As-doped polySi. This effect drastically reduces the number of states available in the conduction band at low energies. The resulting shift of the Fermi level provides a qualitative explanation for the observed puzzling difference between the work-functions of Asand P- doped polySi.

Quantum Size Effect Silicon Structures via Molecularly Self-Assembled Hybrid Templates

2002 ◽  
Vol 728 ◽  
Author(s):  
Elena A. Guliants ◽  
Moises A. Carreon ◽  
Don C. Abeysinghe ◽  
Chunhai Ji ◽  
Wayne A. Anderson ◽  
...  
Keyword(s):  
Thin Film ◽  
Size Effect ◽  
Self Assembly ◽  
Quantum Size Effect ◽  
Inorganic Materials ◽  
Periodic Array ◽  
Atomic Scale ◽  
Quantum Size ◽  
Novel Approach ◽  
Silica Template

AbstractA novel approach for the synthesis of advanced functional inorganic materials with atomic-scale control over the size of periodic features on the sub-30 nm scale is presented. The key innovative aspect of this technique is the direct, bottom-up formation of a two-dimensional periodic array of spatially separated nanostructures in a self-organized thin-film porous template. This thin-film template is fabricated via biologically inspired hierarchical self-assembly of organic surfactant molecules in the presence of inorganic charged silicate species. The removal of organic molecules from such an organic/inorganic hybrid system creates a periodic array of pore channels of ∼3-30 nm diameter inside the thin-film silica template. This porous template is employed as a shadow mask to directly grow various functional nanostructures inside the confined environment of the periodic pore arrays. In the present study, silicon nanostructures were grown inside the templates by both chemical and physical (sputtering) vapor deposition. The quantum size effect was clearly pronounced in the room temperature photoluminescence spectra of the samples prepared by sputtering from a Si target, which makes the approach highly promising for the fabrication of nanoscale optoelectronic devices.

scholarly journals The Influence Of NO/O2 On The NOx Storage Properties Over A Pt-Ba-Ce/γ-Al2O3 Catalyst

2019 ◽  
Vol 17 (1) ◽  
pp. 1459-1465
Author(s):  
Xuedong Feng ◽  
Jing Yi ◽  
Peng Luo
Keyword(s):  
Sol Gel ◽  
Chemical Properties ◽  
No Oxidation ◽  
Test Results ◽  
X Ray Diffraction ◽  
Storage Performance ◽  
Transmission Electron ◽  
Temperature Programmed ◽  
Physical And Chemical ◽  
Al2o3 Catalyst

AbstractWith the purpose of studying the influence of NO/O2 on the NOx storage activity, a Pt-Ba-Ce/γ-Al2O3 catalyst was synthesized by an acid-aided sol-gel method. The physical and chemical properties of the catalyst were characterized by X-ray diffraction (XRD) and Transmission Electron Microscope (TEM) methods. The results showed that the composition of the catalyst was well-crystallized and the crystalline size of CeO2 (111) was about 5.7 nm. The mechanism of NO and NO2 storage and NOx temperature programmed desorption (NO-TPD) experiments were investigated to evaluate the NOx storage capacity of the catalyst. Pt-Ba-Ce/γ-Al2O3 catalyst presented the supreme NOx storage performance at 350℃, and the maximum value reached to 668.8 μmol / gcat. Compared with O2-free condition, NO oxidation to NO2 by O2 had a beneficial effect on the storage performance of NOx. NO-TPD test results showed that the NOx species stored on the catalyst surface still kept relatively stable even below 350℃.

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