Synthesis, Characterization and Evolution Mechanism Study of Semiconductor Nanocrystals

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Synthesis, Characterization and Evolution
Mechanism Study of Semiconductor Nanocrystals
Jiye Fang, University of New Orleans,
DMR-0449580 
High-quality chalcogenide/oxide and
manganese-doped semi- conductor nanocrystals
(NCs) are inspired by thermoelectric and
spintronic applications. Recently, we
successfully synthesized mono- disperse NCs of
PbSe, PbTe, Bi2Te3 and In2O3 with shape- and
size- control by employing a high-temperature
organic solution approach, demonstrating the
feasibility of this synthetic strategy. (1)
Investi- gations of In2O3 NCs (JACS, 127, 5276,
2005, top-left) imply that each NC is a single
crystal with high-crystallinity, and the size of
NCs is tunable. (2) A mechanism study of PbTe
nanocrystalline evolution (JACS, 126, 11798,
2004, top-right) indicates that the shape of PbTe
NCs can be developed from spherical to cubic
structure when certain experimental parameters
are well controlled. (3) A novel method for the
large-scale, shape-controlled synthesis of 1D
corrugated Mn- doped PbSe nanoarrays without
using any capping polymer or ionic surfactant
was developed (JACS, 126, 14816, 2004,
bottom-left). (4) A unique synthesis of
discrete, single-crystal, defect-free and
hexa- gonal Bi2Te3 nanoplatelets was achieved,
and a two-step epitaxial growth of the
cylindrical strings of Bi2Te3 nanoplatelets on
the Te rod surface by packing them along c-axis
in a top-bottom-top- bottom sequence was proposed
as well (JACS, 127, 10112, 2005, bottom-right).
(5) To extend this synthesis approach to III-V
semiconductor system, we are progressively
synthesizing Mn- doped InP and GaP NCs with size-
and shape-control.
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Synthesis, Characterization and Evolution
Mechanism Study of Semiconductor Nanocrystals
Jiye Fang, University of New Orleans,
DMR-0449580