Oxygen-assisted unidirectional growth of CdSe nanorods using a low-temperature redox process.
The role of oxygen in directing the low temperature (125 degrees C), redox-assisted, unidimensional and unidirectional growth of CdSe nanocrystals (NCs) was investigated. In the presence of oxygen, CdSe quantum dots grow selectively along their c axis with little to no change in their width. Reduction of oxygen in the growth medium results in three-dimensional growth. Moreover the one-dimensional growth was found to occur only from one of the two inequivalent polar (0001) facets, as supported by the seeded growth of Cd(x)Hg(1-x)Se onto CdSe seeds. This is in agreement with density functional theory simulations, which indicate that due to selective oxygen passivation growth can occur only along the [0001] direction. The ability to control seeded NC growth with respect to morphology and directionality opens new possibilities toward the low temperature synthesis of complex nanostructures.
Doll
Jonathan D
JD
Nanomaterials Optoelectronics Laboratory (NOEL), Polymer Program, University of Connecticut,Storrs, Connecticut 06269-3136, USA.
Pilania
Ghanshyam
G
Ramprasad
Ramamurthy
R
Papadimitrakopoulos
Fotios
F
D019187:Cadmium Compounds / Q000737:chemistry*; D003080:Cold Temperature; D003460:Crystallization; D053768:Metal Nanoparticles / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission / Q000379:methods; D008956:Models, Chemical; D036103:Nanotechnology / Q000379:methods*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry*; D045663:Quantum Dots; D018036:Selenium Compounds / Q000737:chemistry*; D013696:Temperature
D019187:Cadmium Compounds; D018036:Selenium Compounds; C058667:cadmium selenide; D010100:Oxygen