ZnTe Nanocrystals Research Articles

Combinatorial synthesis of ZnTe nanocrystals in SiO 2 on silicon by ion implantation

In the field of organic chemistry combinatorial synthesis and screening of a large number of compounds is a common method for discovering and optimizing specific chemical and physical properties. Furthermore this approach is well suited when there are no reliable theories for the predictability of the chemical reaction paths and the resulting basic properties. Here we describe the application of the combinatorial synthesis technique on the synthesis of optically active ZnTe nanocrystals buried in SiO 2 on a Si(1 0 0) surface. This and similar materials are of great technical interest, because they enable the combination of quantum dots of direct band gap semiconductor materials with silicon. The redistribution of the implanted constituents before and after annealing is measured by Rutherford-backscattering spectroscopy, transmission electron microscopy and shows a complex concentration distribution pattern strongly influenced by the annealing process gas.

ChemInform Abstract: Size and Shape Controlled ZnTe Nanocrystals with Quantum Confinement Effect.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Convenient Molecular Approach of Size and Shape Controlled ZnSe and ZnTe Nanocrystals

AbstractOur study describes a convenient one-step synthesis of ZnSe and ZnTe nanocrystals (NC) whose sizes and shapes are precisely tuned by varing the growth temperature or stabilizing surfactants. We utilized molecular precursors, bis(phenylselenolate or phenyltellurolato)zinc -N,N,N',N'-tetramethylethylenediamine (TMEDA), which effectively produce 0-dimensional sphere or 1-dimensional nanorods of ZnSe or ZnTe, respectively. Nanocrystals are highly monodispersed and luminescent; the emission wavelength varies over a wide range depending on the particle size. This study constitutes a nice demonstration of direct size and shape controlled synthesis of semiconductor nanocrystals and this method can be extended to the synthesis of nanocrystals of other materials.

Size and shape controlled ZnTe nanocrystals with quantum confinement effect

A simple one-pot synthesis of size and shape controlled ZnTe nanocrystals using a monomeric molecular precursor, [Zn(TePh)2][TMEDA], has been studied by varying the growth temperature or the templating surfactants.

Silicon and zinc telluride nanoparticles synthesized by pulsed laser ablation: size distributions and nanoscale structure

Size distributions of Si and ZnTe nanoparticles produced by low energy density ArF (193 nm) pulsed laser ablation into ambient gases were measured as a function of the gas pressure and target-substrate separation, D ts, using atomic force microscopy (AFM) and high resolution scanning electron microscopy (HRSEM). For low energy density ( E d=1.04 J/cm 2) ablation of Si into He at pressures of 0.5, 1.5, 4 and 10 Torr, large nanoparticles were most numerous at D ts=10 mm, with smaller nanoparticles found at 20 mm and 40 mm. For each D ts value a maximum of the mean nanoparticle diameter occurred for a He pressure near 6 Torr, in contrast to other recent measurements in which the size of Si nanoparticles increased monotonically with the He pressure. High resolution Z-contrast transmission electron microscopy (HRZTEM) and electron energy loss spectroscopy (EELS) revealed that ZnTe nanoparticles formed by ablation into nitrogen at E d=0.74 J/cm 2 consisted of a crystalline ZnTe core surrounded by an amorphous ZnO shell. Growth defects and surface steps were clearly visible in the ZnTe crystalline core. The dependencies of the mean diameter of ZnTe nanocrystals on nitrogen pressure and D ts were qualitatively similar to those found for Si in He.

Determination of the Pressure Dependence of Band‐Structure Parameters by Two‐Photon Spectroscopy

AbstractTwo‐photon spectroscopy has been used to determine the pressure dependence of band‐structure parameters such as band gap, exciton binding energy, biexciton binding energy, exchange energy, and Luttinger parameters. Compared to linear spectroscopy it yields not only a higher precision, but is often able to determine a larger number of parameters. Results are presented for ZnTe and CuCl nanocrystals in a LiCl matrix.