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Updated: May 25, 2026
12:56
Seeded Synthesis of CdSe/CdS Rod and Tetrapod Nanocrystals
Published on: December 11, 2013
Thermally induced structural and morphological changes of CdSe/CdS octapods
Bart Goris1, Marijn A Van Huis, Sara Bals
1EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium.
Small (Weinheim an Der Bergstrasse, Germany)
|February 1, 2012
Summary
Branched nanostructures like cadmium selenide/sulfide octapods exhibit varying thermal stability. Heating causes shape changes, cadmium segregation, and core growth, impacting their use in devices.
Area of Science:
- Materials Science
- Nanotechnology
- Solid State Physics
Background:
- Branched nanostructures offer unique optical and electronic properties.
- Thermal stability is crucial for integrating nanostructures into applications like photovoltaics.
Purpose of the Study:
- To investigate the thermal stability and heat-induced shape changes of heterogeneous cadmium selenide/sulfide (CdSe/CdS) octapods.
- To understand how different domains within the nanostructure respond to thermal stress.
Main Methods:
- Heating octapods from room temperature to 700 °C.
- Utilizing analytical and tomographic transmission electron microscopy (TEM) for in-situ observation.
- Analyzing structural and compositional changes at various annealing temperatures.
Main Results:
- Observed cadmium (Cd) segregation into droplets at low temperatures, indicating non-stoichiometric composition.
- Noticed rounding of pod tips and growth of the zinc blende core at the expense of wurtzite pods upon further heating.
- Documented sublimation of octapods at 500-700 °C and identified lower thermal stability in pods exposed to vacuum.
Conclusions:
- CdSe/CdS octapods display differential thermal stability between their core and pod domains.
- Heating induces significant structural transformations, including segregation, phase growth, and sublimation.
- Understanding these thermal behaviors is essential for designing robust nanostructured materials for electronic and photovoltaic applications.
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