The Use of Single-Source Precursors in Nanoparticle Synthesis - Semiconductor Quantum Dots: Organometallic and Inorganic Synthesis - page 245

solution-based reactions with azides). The ambient-pressure route produced
small particles ( ca. 3 nm) with poor crystallinity relative to the high-pressure
route, possibly due to the high-pressure route

s constant exposure to high-
pressure nitrogen as opposed to the constantly vented low-pressure
synthesis. The particles appeared larger and more aggregated when
compared to the II

'

V nanomaterials. Notably,
the use of the amine reportedly resulted in the decomposition of the nitride
structures, resulting in indium metal. 145
The single-source route does have its limitations. The stoichiometry of the
particles prepared by just one precursor cannot be easily manipulated, unlike
the binary approach where altering the ratio of precursors can markedly
a

- VI analogues, or even other III -

d n 1 y 4 n g | 4

ect the optical properties. 146 The development of the SILAR route described
in Chapter 5 is an excellent example of where a speci

c nanoparticle struc-
ture can be prepared by the addition of binary precursors. The preparation of
single-source precursors is, in some cases, more di



cult than the prepara-
tion of nanoparticles themselves from the simple binary routes, although
some new phases of materials may only be accessible through single-source
complexes. The chemistry is undoubtedly di

erent for single-source and
binary approaches and this may impact on the resulting materials, and one
has to choose the optimum approach as be ts the situation and the nano-



particles desired.

References
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.

S, Se, Te) materials using
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3. For example, see: P. O

¼

' Brien and R. Nomura, J. Mater. Chem., 1995, 5,

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