Binary nanocrystal superlattices, that is, ordered structures of two sorts of nanocolloids, hold promise for a series of functional materials with novel collective properties. Here we show that based on electron tomography a comprehensive, quantitative, three-dimensional characterization of these systems down to the single nanocrystal level can be achieved, which is key in understanding the eme...

In this letter, isolated Si nanocrystal has been formed by dewetting process with a thin silicon dioxide layer on top. Scanning capacitance microscopy and spectroscopy were used to study the memory properties and charge effect in the Si nanocrystal in ambient temperature. The retention time of trapped charges injected by different direct current (DC) bias were evaluated and compared. By ramp pr...

The size dependence of the quantized energies of elementary excitations is an essential feature of quantum nanostructures, underlying most of their applications in science and technology. Here we report on a fundamental property of impurity states in semiconductor nanocrystals that appears to have been overlooked--the anticrossing of energy levels exhibiting different size dependencies. We show...

Si nanocrystals embedded in SiO2 doped with P and Au at concentrations in the range of 1 10–3 10 cm 3 exhibit photoluminescence quenching. Upon increasing the Au concentration, a gradual decrease in nanocrystal photoluminescence intensity is observed. Using a statistical model for luminescence quenching, we derive a typical radius of 3 nm for nanocrystals luminescing around 800 nm. Au doping al...

Zeolite is a crystalline alumino-silicate microporous material, which has been widely used as ion-exchangers, adsorbent and catalyst.
 Recently, several researches highlights the progress of zeolite-based catalysts in CO2 conversion to valuable products.
 In present work, hydrothermal synthesis mordenite zeolite crystals, with composition chemical products Al2O3, 12.5 SiO2,2.4 NaOH, 1...

A nanocrystal memory using CoSi2/Si hetero-nanocrystals as floating gate was proposed. Numerical investigations on the writing, erasing and retention were performed. The hetero-structure provides an extra quantum well for the charge to achieve much longer retention time while maintains a writing/erasing speed similar to that of Si nanocrystal memory. 2005 Elsevier Ltd. All rights reserved. PACS...

The mechanical stability of nanocrystal films is critical for applications, yet largely unexplored. Raman microprobe analysis used here to probe the nanocrystal cores of thick, fractured electrophoretically deposited films of 3.2 nm diameter CdSe nanocrystals measures approximately 2.5% in-plane tensile strain in cores of unfractured films. The crack dimensions determine the overall in-plane fi...