Homogeneously alloyed CdSxSe1-x nanocrystals: synthesis, characterization, and composition/size-dependent band gap.
Alloy nanocrystals provide an additional degree of freedom in selecting desirable properties for nanoscale engineering because their physical and optical properties depend on both size and composition. We report the pyrolytic synthesis of homogeneously alloyed CdS(x)Se(1-x) nanocrystals in all proportions. The nanocrystals are characterized using UV-visible absorption spectroscopy, transmission electron microscopy, X-ray diffractrometry, and Rutherford backscattering spectrometry to determine precisely structure, size, and composition. The dependence of band gap on nanocrystal size and composition is elucidated, yielding a bowing constant of 0.29, in agreement with bulk values. In addition, the morphology of the resultant nanocrystals can be altered by changing the reaction conditions, generating structures ranging from homogeneous, spherical nanocrystals to one-dimensional gradient nanorods.
Swafford
Laura A
LA
Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235-1822, USA.
Weigand
Lauren A
LA
Bowers
Michael J
MJ
McBride
James R
JR
Rapaport
Jason L
JL
Watt
Tony L
TL
Dixit
Sriram K
SK
Feldman
Leonard C
LC
Rosenthal
Sandra J
SJ
D000497:Alloys / Q000737:chemistry*; D019187:Cadmium Compounds / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D012643:Selenium / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D013455:Sulfur / Q000737:chemistry*; D014961:X-Ray Diffraction
D000497:Alloys; D019187:Cadmium Compounds; D010087:Oxides; C029663:cadmium oxide; D013455:Sulfur; D012643:Selenium