2InCl 3 þ 2As þ 6KBH 4 ƒƒƒƒƒƒƒ ƒ!
ethylenediamine
160 C
2InAs þ 6KCl þ 6BH 3 þ 3H 2
ð9Þ
TEM shows that the products are polycrystalline fibers or near-single-crystal
whiskers with widths of 15–100 nm and lengths of 150–1000 nm (Figure 7.10E).
When the reaction temperature was reduced to 120
C, which is below the melting
point of indium (156.6
C), spherical InAs nanocrystals of 20–50 nm were obtained (Figure 7.10D). However, there is trace indium co-existing in the products,
indicating that the reaction proceeds through a metallic indium intermediate.
Similarly, as shown in Reactions (10) and (11), under high-intensity ultrasonic
irradiation, InP nanocrystallites were synthesized in ethanol/benzene mixed solvent at room temperature [46].
2InCl 3 þ 6KBH 4 ƒƒƒƒƒƒƒƒƒƒ ƒ!
ultrasonic irradiation 2In þ 6KCl þ 6BH 3 þ 3H 2
ð10Þ
4In þ P 4 ƒƒƒƒƒƒƒƒƒ!
room temperature 4InP
ð11Þ
The XRD pattern (Figure 7.11(a)) indicates that the product is sphalerite-type cubic
InP. The TEM images (Figure 7.11(b)) show that the products are 9 nm spherical
Fig. 7.9. XRD pattern (a) and TEM images (b) of the as-prepared nanocrystalline AlN.
7 Solvothermal Synthesis of Non-Oxide Nanomaterials
178