CdS/Cyclohexylamine Inorganic–Organic Hybrid Semiconductor Nanofibers with Strong Quantum Confinement Effect

Inorganic–organic hybrid semiconductor nanofibers of CdS/CHA (CHA = cyclohexylamine) were successfully synthesized by a simple solvothermal method. The fibers obtained had average diameter of 20 nm and length of several micrometers. In these fibers, periodic layer-like sub-nanometer structures with thickness of ∼3 nm were identified by high-resolution transmission electron microscope (HR-TEM). The absorption of the hybrids exhibited a large blue-shift in contrast to the bulk, which was attributed to strong quantum confinement effect (QCE) induced by internal sub-nanometer structures. Pure hexagonal wurtzite CdS (H-CdS) nanorods were also obtained by extracting the CdS/CHA hybrids with dimethyl formamide (DMF). The rods obtained had average diameter of 20 nm and length of 200 nm. A CdS/CHA/polyvinyl alcohol (PVA) composite film emitting white light was prepared by spin coating.

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[ZnSe(dbn)1/2] and [ZnSe(hda)1/2]: Two New Members of Inorganic-Organic Hybrid Semiconductor Nanocomposites Exhibiting A Strong Quantum Confinement Effect

MRS Proceedings ◽

10.1557/proc-728-s1.7 ◽

2002 ◽

Vol 728 ◽

Cited By ~ 7

Author(s):

Xiaoying Huang ◽

Jing Li

Keyword(s):

Quantum Confinement ◽

Quantum Confinement Effect ◽

Diffraction Method ◽

Blue Shift ◽

Confinement Effect ◽

X Ray Diffraction ◽

Orthorhombic Crystal ◽

New Members ◽

Organic Hybrid ◽

Semiconductor Nanocomposites

AbstractTwo new inorganic-organic hybrid II-VI semiconductor nanostructures have been synthesized by solvothermal reactions. These nanostructures consist of inorganic 2∞[ZnSe] layers and organic bridging diamine molecules as spacers. The crystal structures of [ZnSe(dbn)1/2](1, dbn = 1,4-diaminobutane) and [ZnSe(hda)1/2](2, hda = 1,6-hexanediamine) have been determined by the powder X-ray diffraction method. They are isostructural and crystallize in the orthorhombic crystal system, space group Pbca(No.62), Z = 4. Crystal data for 1: a = 6.646(3), b = 6.473(3), c = 22.31(1) Å, V = 961.2(13) Å3, for 2: a = 6.6252(18), b = 6.4505(17), c = 27.138(7) Å, V = 1159.8(9) Å3. The optical absorption experiments show that both 1 and 2 generate a very large blue shift in the absorption edge (1.5-1.6 eV) due to a strong quantum confinement effect (QCE). Thermogravimetric behavior of both compounds has also been investigated.

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Synthesis and Characterization of Mn2+ Doped ZnS Using Reverse Miceller Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.970.283 ◽

2014 ◽

Vol 970 ◽

pp. 283-287

Author(s):

Rahizana Mohd Ibrahim ◽

Markom Masturah ◽

Huda Abdullah

Keyword(s):

Quantum Confinement ◽

Quantum Confinement Effect ◽

Blue Shift ◽

Band Gap Energy ◽

Confinement Effect ◽

X Ray Diffraction ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Size Of Particles ◽

Absorbance Spectra

In this work we synthesized the monodisperse of Zn1-xMnxS with x =0.00,0.02,0.04,0.06,0.08 and 0.10 nanoparticles by reverse micelle method using sodium bis (2-ethylhexyl) sulfosuccinate (AOT) as surfactant. The prepared particles were characterized using UV-Visible Spectroscopy, X-ray diffraction (XRD), Transmission Electron Microscopy (TEM) and Photoluminescence (PL) for size, morphology and optical of the samples .UV-vis absorbance spectra for all of the synthesized nanoparticles show the maximum absorption for all samples is observed at range 210 - 300 nm . The absorption edge shifted to lower wavelengths when doping with ion Mn as per UV-Vis spectroscopy. The band gap energy values were increase from 4.50eV to 4.90 eV. This blue shift is attributed to the quantum confinement effect. The size of particles is found to be 3-5nm range. The Mn2+ doped ZnS nanoparticles using reverse micelles method shows the enhance of PL intensity results in monodisperse nanoparticles. Keywords: Nanoparticles; UV-vis absorbance spectra; quantum confinement effect; photoluminescence.

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QUANTUM CONFINEMENT EFFECT IN HgTe NANOCRYSTALS AND VISIBLE LUMINESCENCE

International Journal of Nanoscience ◽

10.1142/s0219581x04002176 ◽

2004 ◽

Vol 03 (03) ◽

pp. 393-401 ◽

Cited By ~ 10

Author(s):

S. RATH ◽

A. K. DASH ◽

S. N. SAHU ◽

S. NOZAKI

Keyword(s):

Valence Band ◽

Quantum Confinement ◽

Quantum Confinement Effect ◽

Free Exciton ◽

Confinement Effect ◽

Electrochemical Technique ◽

Cubic Phase ◽

Exciton Transition ◽

Mercury Telluride ◽

Transmission Electron

Mercury Telluride ( HgTe ) nanocrystals with a mean size of 5.35 nm have been synthesized by an electrochemical technique. Structural analysis by transmission electron microscopy and glancing angle X-ray diffraction studies indicate the presence of cubic phase HgTe nanocrystals in the deposit. Optical absorption measurements reveal two well resolved excitonic peaks around 578.5 nm and 550 nm attributed to heavy hole valence band (HVB)–conduction band (CB) and light hole valence band (LVB)–CB transitions, respectively, and suggest a band opening of bulk inverted narrow band gap HgTe as a result of strong quantum confinement effect (QCE). Visible photoluminescence (PL) of HgTe nanocrystals indicates free exciton transition around 579.5 nm as observed from the PL measurement at 300 K along with a bound exciton dominated band around 588 nm. Micro-Raman measurements at 300 K indicate the 1LO vibrational mode at 142.6 cm-1 shifted by 6 cm-1 from its standard bulk value and confirm the QCE.

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Nanostructured crystals: An unprecedented class of hybrid semiconductors exhibiting structure-induced quantum confinement effect and systematically tunable properties

10.1093/oxfordhb/9780199533053.013.16 ◽

2017 ◽

Author(s):

Jing Li ◽

Xiao-Ying Huang

Keyword(s):

Quantum Confinement ◽

Quantum Confinement Effect ◽

Three Dimensional ◽

Hybrid Nanostructures ◽

Confinement Effect ◽

Design And Synthesis ◽

Organic Hybrid ◽

Expansion Behavior ◽

Dimensional Network ◽

Hybrid Semiconductors

This article describes the structure-induced quantum confinement effect in nanostructured crystals, a unique class of hybrid semiconductors that incorporate organic and inorganic components into a single-crystal lattice via covalent (coordinative) bonds to form extended one-, two- and three-dimensional network structures. These structures are comprised of subnanometer-sized II-VI semiconductor segments (inorganic component) and amine molecules (organic component) arranged into perfectly ordered arrays. The article first provides an overview of II-VI and III-V semiconductors, II-VI colloidal quantum dots, inorganic-organic hybrid materials before discussing the design and synthesis of I-VI-based inorganic-organic hybrid nanostructures. It also considers the crystal structures, quantum confinement effect, bandgaps, and optical properties, thermal properties, thermal expansion behavior of nanostructured crystals.

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Correlation Between Microstructure and Optical Properties of ZnO Based Nanostructures Grown by MOCVD

MRS Proceedings ◽

10.1557/proc-1074-i07-08 ◽

2008 ◽

Vol 1074 ◽

Author(s):

Farid Falyouni ◽

Julien Barjon ◽

Vincent Sallet ◽

Alain Lusson ◽

Guy Garry ◽

...

Keyword(s):

Low Temperature ◽

Structural Properties ◽

Quantum Confinement ◽

Dopant Concentration ◽

Quantum Confinement Effect ◽

Chemical Vapor ◽

Blue Shift ◽

Transmission Electron ◽

Optical Signature ◽

Excitonic Emission

ABSTRACTThe correlation between structural properties of ZnO sharp conical needles grown by Metallorganic Chemical Vapor Deposition (MOCVD) on sapphire substrate and their optical signature measured by low temperature cathodoluminescence (CL) is investigated. Transmission Electron Microscopy (TEM) shows the excellent structural properties of these needles from their base up to the end of the tip. In order to probe the emission of the needles along their length, UV CL mapping has been performed at low temperature on a single needle previously characterized by TEM. A clear blue shift of 25meV is observed for the excitonic emission close to the needle tip. This shift is too high to be fully attributed to quantum confinement. Although, it qualitatively agrees with previous observations which assigned it to a surface contribution becoming dominant upon size shrinking, the effect is less pronounced. The results are discussed in term of surface quality and other possible contributions associated to a decrease of the n-dopant concentration and to quantum confinement effect close to the tip.

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Growth and Optical Properties of SnO2 Ultra-Small Nanorods by the Novel Micelle Techniques

MRS Proceedings ◽

10.1557/proc-1087-v03-29 ◽

2008 ◽

Vol 1087 ◽

Author(s):

Satchidananda Rath ◽

Shinji Nozaki ◽

Hiroshi Ono ◽

Kazuo Uchida ◽

Satoshi Khojima

Keyword(s):

Quantum Confinement ◽

Photoluminescence Spectrum ◽

Tin Dioxide ◽

Optical Band Gap ◽

Quantum Confinement Effect ◽

Average Diameter ◽

The Novel ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron

AbstractTin-dioxide (SnO2) ultra-small nanorods (UNR) have been successfully synthesized using the novel micellar technique. From transmission electron microscopy, the average diameter and length of the UNRs are estimated to be 1.3 nm and 5.0 nm, respectively. The crystal structure of the SnO2 UNRs was found to be tetragonal from the glazing incidence x-ray diffraction. The optical band gap estimated from the absorption spectrum is blue-shifted by 1 eV from that of bulk (3.64 eV). The photoluminescence spectrum shows two groups of peaks each with several fine peaks, one in the wavelength range of 270 – 370 nm and the other in the range of 380 – 500 nm which are due to the strong quantum confinement effect.

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CdS/Cyclohexylamine Inorganic–Organic Hybrid Semiconductor Nanofibers with Strong Quantum Confinement Effect

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.180 ◽

2008 ◽

Vol 8 (8) ◽

pp. 3914-3920 ◽

Cited By ~ 8

Author(s):

Libo Fan ◽

Hongwei Song ◽

Haifeng Zhao ◽

Guohui Pan ◽

Lina Liu ◽

...

Keyword(s):

Quantum Confinement ◽

Quantum Confinement Effect ◽

Confinement Effect ◽

Organic Hybrid

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Low-Temperature Synthesis of Nearly Monodisperse ZnS Nanospheres Using a Facile Solution-Phase Approach

Australian Journal of Chemistry ◽

10.1071/ch06170 ◽

2006 ◽

Vol 59 (11) ◽

pp. 791 ◽

Cited By ~ 3

Author(s):

Weizhi Wang ◽

Liyong Chen ◽

Shutao Wang ◽

Baojuan Xi ◽

Shenglin Xiong ◽

...

Keyword(s):

Low Temperature ◽

Quantum Confinement ◽

Quantum Confinement Effect ◽

Reaction Times ◽

Blue Shift ◽

Average Diameter ◽

Solution Phase ◽

Sulfur Source ◽

Low Temperature Synthesis ◽

Ft Ir

This paper describes a facile and controllable solution-phase process for the preparation of nearly monodisperse ZnS nanospheres, with an average diameter of 150 nm, at a low temperature (80°C). Thiourea is used both as a sulfur source and as a capping ligand which can direct initially formed ZnS particles to aggregate into nanospheres. The average diameter of ZnS nanospheres could be readily controlled by varying the reaction time. On the basis of the results of different reaction times and Fourier transform infrared (FT-IR) spectrum analysis, a possible aggregation mechanism to form ZnS nanospheres is proposed. The UV-vis absorption spectra of the obtained ZnS nanospheres exhibits an obvious blue shift due to the quantum confinement effect.

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