trol a potentiostat and a second controls the ultrasonic processor, which is adapted
to work in the pulse mode.
The sonoelectrochemical deposition of CdSe nanoparticles is carried out
from an aqueous solution of CdSO 4 , complexed with potassium nitrilotriacetate
(N(CH 2 CO 2 K) 3 ) NTA as a source for Cd, and a selenosulfate solution, (Na 2 SeSO 3 ),
as source for Se. The CdSe crystal size could be varied from X-ray amorphous up to
9 nm by controlling the various electrodeposition and sonic parameters. The effects of various electrodeposition and sonic parameters on the properties of CdSe
nanoparticles are presented in Table 6.3.
Fig. 6.8. Schematic of sonoelectrochemical deposition set-up
and the sonic and electrochemical waveforms.
Tab. 6.3. Effect of various deposition parameters on the CdSe nanoparticles properties in
pulsed sonoelectrochemical synthesis.
Variable Parameter
Crystal Size (nm)
Bandgap E g (eV)
Temperature (
C)
5
25
75
4.5
5.5
6.5
2.10
2.10
1.93
Ultrasound Intensity (W)
0
10
60
Continuous ultrasound
9
10
4
Amorphous
1.90
1.85
2.15
–
Current Pulse Width (sec)
0.68
0.34
0.11
7
5
4
1.95
2.05
2.15
6 Sonochemistry and Other Novel Methods Developed for the Synthesis of Nanoparticles
150