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Synthesis and Characterization of Supramolecular Colloids
Published on: April 22, 2016
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Synthesis and Characterization of Controlled Size CdSe Quantum Dots by Colloidal Method.
Ganesh R Bhand1, Manorama G Lakhe1, Ashwini B Rohom1
1Department of Physics, Savitribai Phule Pune University, Pune 411007, India.
Journal of Nanoscience and Nanotechnology
|February 15, 2018
Summary
Highly luminescent cadmium selenide (CdSe) quantum dots (QDs) were synthesized using a colloidal method. Growth temperature controlled QD size and optical properties, with cubic structures confirmed by XRD and TEM.
Area of Science:
- Materials Science
- Nanotechnology
- Solid State Physics
Background:
- Quantum dots (QDs) offer tunable optical and electronic properties.
- Cadmium selenide (CdSe) QDs are promising for optoelectronic applications.
- Controlling QD size and surface properties is crucial for performance.
Purpose of the Study:
- To synthesize monodispersed, highly luminescent CdSe quantum dots (QDs) via a single-pot colloidal reaction.
- To investigate the effect of growth temperature on the structural, morphological, compositional, and optical properties of CdSe QDs.
- To characterize the synthesized QDs using various spectroscopic and microscopic techniques.
Main Methods:
- Single-pot colloidal reaction method for CdSe QD synthesis.
- Characterization using X-ray diffraction (XRD), Raman Spectroscopy, Transmission Electron Microscopy (TEM), Energy Dispersive Spectroscopy (EDS), UV-Visible absorption, and Photoluminescence (PL) spectroscopy.
- Systematic variation of reaction temperature from 110 °C to 260 °C.
Main Results:
- Monodispersed CdSe QDs with sizes ranging from 2-4.5 nm were successfully synthesized.
- Growth temperature significantly influenced QD size and optical properties, shifting emission from 460 nm to 575 nm.
- XRD and HRTEM confirmed a cubic crystal structure, while EDS indicated near-stoichiometric composition.
- PL spectra revealed surface trap-states at lower synthesis temperatures.
Conclusions:
- The colloidal reaction method enables controlled synthesis of luminescent CdSe QDs.
- Growth temperature is a critical parameter for tuning QD size, optical properties, and minimizing surface trap states.
- The synthesized CdSe QDs exhibit promising structural and optical characteristics for potential applications.
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