Size Tunablity of CdTe Crystallites in Dendrimer Nanocomposites and Temperature Dependent Focusing of Size Distribution

$113.00 plus tax (Refund Policy)

Buy Article:

Abstract:

CdTe/Dendrimer nanocomposites have been synthesized for the first time in aqueous and non-aqueous media using PAMAM dendrimer (Generation 5.0). The average size of the as-prepared nanocomposites, as determined from dynamic light scattering (DLS) measurements, was found to be typically 182 nm and 23 nm in water and methanol, respectively under identical conditions of temperature (5 °C) and reagent ratio (Cd2+:Te2−, 1:0.5). The size of CdTe NPs within the nanocomposites, was found to be 3.1 and 2.8 nm for the aforementioned samples determined from optical absorption spectra using tight binding approximation. The NPs possess good degree of cystallinity as discernible from the lattice fringes in high-resolution transmission electron microscopic (HRTEM). Transmission electron microscopic (TEM) image and the cubic crystal phase was ascertained from the small area electron diffraction (SAED) pattern. Analysis of FTIR data suggests that CdTe NPs are bound to the surface amine groups as well as –NHCO– moieties lying in the interior of dendrimer structure. The present work demonstrates how the quality of the CdTe NPs formed within the dendrimer matrix can be nicely tuned by varying the parameters, namely, temperature, molar ratio of Cd2+:Te2− and pH. Changing of Cd2+:Te2− ratio of 1:1 to 1:0.5, decreased the average particle size from 5.0 nm to 3.4 nm with concomitant narrowing of size distribution by ∼35% at 10 °C. On lowering down the synthesis temperature (25 °C→5 °C), the average particle size remained unaffected while the size distribution became sharply focused. However, the extent of focusing was found to be more in methanol (40%) than that in water (30%).

Keywords: CDTE; CRYSTALLITES; DENDRIMER; NANOCOMPOSITES

Document Type: Research Article

DOI: http://dx.doi.org/10.1166/jnn.2008.323

Publication date: November 1, 2008

More about this publication?
  • Journal for Nanoscience and Nanotechnology (JNN) is an international and multidisciplinary peer-reviewed journal with a wide-ranging coverage, consolidating research activities in all areas of nanoscience and nanotechnology into a single and unique reference source. JNN is the first cross-disciplinary journal to publish original full research articles, rapid communications of important new scientific and technological findings, timely state-of-the-art reviews with author's photo and short biography, and current research news encompassing the fundamental and applied research in all disciplines of science, engineering and medicine.
  • Editorial Board
  • Information for Authors
  • Subscribe to this Title
  • Terms & Conditions
  • ingentaconnect is not responsible for the content or availability of external websites
Related content

Tools

Favourites

Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more