Synthesis of High Quality Zinc Blende CdSe Nanocrystals

2005 ◽  
Vol 109 (21) ◽  
pp. 10533-10537 ◽  
Author(s):  
Mona B. Mohamed ◽  
Dino Tonti ◽  
Awos Al-Salman ◽  
Abdelkrim Chemseddine ◽  
Majed Chergui
Keyword(s):  
Cdse Nanocrystals ◽  
High Quality ◽  
Zinc Blende

Synthesis of high quality zinc-blende CdSe nanocrystals and their application in hybrid solar cells

2006 ◽  
Vol 17 (18) ◽  
pp. 4736-4742 ◽  
Author(s):  
Lili Han ◽  
Donghuan Qin ◽  
Xi Jiang ◽  
Yanshan Liu ◽  
Li Wang ◽  
...  
Keyword(s):  
Solar Cells ◽  
Cdse Nanocrystals ◽  
Hybrid Solar Cells ◽  
High Quality ◽  
Zinc Blende

Phosphine-Free Synthesis of High Quality CdSe Nanocrystals and Their Optical Properties

2010 ◽  
Vol 26 (03) ◽  
pp. 691-694
Author(s):  
ZHAO Hui-Ling ◽  
◽  
◽  
SHEN Huai-Bin ◽  
WANG Hong-Zhe ◽  
...  
Keyword(s):  
Optical Properties ◽  
Cdse Nanocrystals ◽  
High Quality

Synthesis of Mn-doped zinc blende CdSe nanocrystals

2007 ◽  
Vol 90 (17) ◽  
pp. 173111 ◽  
Author(s):  
Woo-Chul Kwak ◽  
Yun-Mo Sung ◽  
Tae Geun Kim ◽  
Won-Seok Chae
Keyword(s):  
Cdse Nanocrystals ◽  
Zinc Blende ◽  
Mn Doped

scholarly journals Synthesis of High-Quality Carboxyl End-Functionalized Poly(3-hexylthiophene)/CdSe Nanocomposites

2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
He-Ping Shi ◽  
Da-Wei Lin ◽  
Rui-feng Wu
Keyword(s):  
Particle Size ◽  
Charge Transfer ◽  
Crystalline Structure ◽  
Environmentally Friendly ◽  
Cdse Nanocrystals ◽  
High Quality ◽  
Efficient Charge ◽  
Controllable Particle Size ◽  
Better Than

Carboxyl end-functionalized poly(3-hexylthiophene) (P3HT-COOH) was grafted chemically with CdSe nanocrystals (NCs) by a phosphine-free method. The particle quality of P3HT-COOH/CdSe nanocomposites was better than that of P3HT/CdSe nanocomposites, which were synthesized using the same method. Nanocrystals with controllable particle size exhibited a wurtzite crystalline structure and showed excellent nanocrystal dispersion in the P3HT-COOH matrix. Photoluminescence (PL) characterization performed on nanocomposites suggested the efficient charge transfer at the P3HT-COOH/CdSe interface. This approach based on the phosphine-free method is not only environmentally friendly but also highly efficient.

Electrophoretic Deposition of CdSe Nanocrystal Films on Conducting Electrodes

2002 ◽  
Vol 737 ◽  
Author(s):  
Mohammad A. Islam ◽  
Yuqi Xia ◽  
Benjamin J. Kraines ◽  
Irving P. Herman
Keyword(s):  
Cdse Nanocrystals ◽  
Large Area ◽  
High Quality ◽  
Dc Voltage ◽  
Dense Arrays ◽  
Dc Electric Field ◽  
Nanocrystal Films ◽  
Glass Electrodes ◽  
Equal Thickness ◽  
Dark Room

ABSTRACTA dc electric field is used to attract thermally charged CdSe nanocrystals in solution to rapidly form large-area, micron-thick films of equal thickness on both electrodes. A pair of Au-on-Si or conducting ITO-on-glass electrodes was submerged in the nanoparticle solution and a dc voltage was applied in a dark room. Uniform, robust, very smooth, and apparently identical films formed on both electrodes. Photoluminescence and absorption of the films showed that they are indeed made of dense arrays of individual nanocrystals. The deposition implies there are both positively and negatively thermally charged dots in solution. These high quality dense arrays of the nanoparticles could be useful in several applications.

scholarly journals Unraveling the Growth Mechanism of Magic-Sized Semiconductor Nanocrystals

2020 ◽  
Author(s):  
Aniket S. Mule ◽  
Sergio Mazzotti ◽  
Aurelio A. Rossinelli ◽  
Marianne Aellen ◽  
P. Tim Prins ◽  
...  
Keyword(s):  
Growth Mechanism ◽  
Surface Reaction ◽  
Size Range ◽  
Semiconductor Nanocrystals ◽  
Nucleation Theory ◽  
Classical Nucleation Theory ◽  
Cdse Nanocrystals ◽  
Layer By Layer ◽  
Zinc Blende ◽  
Kinetic Barriers

Magic-sized clusters (MSCs) of semiconductor are typically defined as specific molecular-scale arrangements of atoms that exhibit enhanced stability. They often grow in discrete jumps, creating a series of crystallites, without the appearance of intermediate sizes. However, despite their long history, the mechanism behind their special stability and growth remains poorly understood. This is particularly true considering experiments that have shown discrete evolution of MSCs to sizes well beyond the “cluster” regime and into the size range of colloidal quantum dots. Here, we study the growth of these larger magic-sized CdSe nanocrystals to unravel the underlying growth mechanism. We first introduce a synthetic protocol that yields a series of nine magic-sized nanocrystals of increasing size. By investigating these crystallites, we obtain important clues about the mechanism. We then develop a microscopic model that uses classical nucleation theory to determine kinetic barriers and simulate the growth. We show that magic-sized nanocrystals are consistent with a series of zinc-blende crystallites that grow layer by layer under surface-reaction-limited conditions. They have a tetrahedral shape, which is preserved when a monolayer is added to any of its four identical facets, leading to a series of discrete nanocrystals with special stability. Our analysis also identifies strong similarities with the growth of semiconductor nanoplatelets, which we then exploit to increase further the size range of our magic-sized nanocrystals. Although we focus here on CdSe, these results reveal a fundamental growth mechanism that can provide a different approach to nearly monodisperse nanocrystals.

scholarly journals Revealing the Surface Structure of CdSe Nanocrystals by Dynamic Nuclear Polarization-Enhanced 77Se and 113Cd Solid-State NMR Spectroscopy

2021 ◽  
Author(s):  
Yunhua Chen ◽  
Rick Dorn ◽  
Michael Hanrahan ◽  
Lin Wei ◽  
Rafael Blome-Fernandez ◽  
...  
Keyword(s):  
Solid State ◽  
Dynamic Nuclear Polarization ◽  
Solid State Nmr ◽  
Nuclear Polarization ◽  
Surface Structures ◽  
Cdse Nanocrystals ◽  
Magic Angle ◽  
Cross Polarization ◽  
Zinc Blende ◽  
Detailed Surface

<p>Dynamic nuclear polarization (DNP) solid-state NMR (SSNMR) spectroscopy was used to obtain detailed surface structures of zinc blende CdSe nanocrystals (NCs) with plate or spheroidal morphologies and which are capped by carboxylic acid ligands. 1D <sup>113</sup>Cd and <sup>77</sup>Se cross-polarization magic angle spinning (CPMAS) NMR spectra revealed distinct signals from Cd and Se atoms on the surface of the NCs, and those residing in bulk-like environments below the surface. <sup>113</sup>Cd cross-polarization magic-angle-turning (CP-MAT) experiments identified CdSe<sub>3</sub>O, CdSe<sub>2</sub>O<sub>2</sub>, and CdSeO<sub>3</sub> Cd coordination environments on the surface of the NCs, where the oxygen atoms are presumably from coordinated carboxylate ligands. The sensitivity gain from DNP enabled natural isotopic abundance 2D homonuclear <sup>113</sup>Cd-<sup>113</sup>Cd and <sup>77</sup>Se-<sup>77</sup>Se and heteronuclear <sup>113</sup>Cd-<sup>77</sup>Se scalar correlation solid-state NMR experiments that reveal the connectivity of the Cd and Se atoms. Importantly, <sup>77</sup>Se{<sup>113</sup>Cd} scalar heteronuclear multiple quantum coherence (<i>J</i>-HMQC) experiments were used to selectively measure one-bond <sup>77</sup>Se-<sup>113</sup>Cd scalar coupling constants (<sup>1</sup><i>J</i>(<sup>77</sup>Se, <sup>113</sup>Cd)). With knowledge of <sup>1</sup><i>J</i>(<sup>77</sup>Se, <sup>113</sup>Cd), heteronuclear <sup>77</sup>Se{<sup>113</sup>Cd} spin echo (<i>J</i>-resolved) NMR experiments were then used to determine the number of Cd atoms bonded to Se atoms and vice versa. The <i>J</i>-resolved experiments directly confirmed that major Cd and Se surface species have CdSe<sub>2</sub>O<sub>2</sub> and SeCd<sub>4</sub> stoichiometries, respectively. Considering the crystal structure of zinc blende CdSe, and the similarity of the solid-state NMR data for the platelets and spheroids, we conclude that the surface of the spheroidal CdSe NCs is primarily composed of {100} facets. The methods outlined here will generally be applicable to obtain detailed surface structures of various main group semiconductors.</p>

Sign in / Sign up

Export Citation Format

Share Document