Cu(2)O nanopowders have been prepared by ultrasound-assisted electrochemistry with a potentiostatic set-up. Their composition has been determined by X-ray diffraction and energy dispersive X-ray spectroscopy. Transmission electron microscopy and centrifugation analyses indicate that the nanopowders consist of agglomerates of variable nanometric diameter grain. Most of particles have a diameter of 8 nm whatever the electrodeposition potential. The influence of the parameters of electrochemical and ultrasonic pulses on the particle diameter was also studied. The specific surface areas determined by Brunauer-Emmet-Teller (BET) model are very high with a value close to 2000 m(2)g(-1).

Morphological development during electrocrystallization of cuprous oxide crystals has been reported. Studies have been focused on the effects of magnetohydrodynamic convection generated by superimposition of a high magnetic field up to 12 T. Variation of the crystal morphology from dense to labyrinthine and finally very highly porous structure with magnetic field has been obtained, whereas no change in the crystallization growth envelope was shown. Here crystals grown under microconvection induced by magnetic field are different because of changes in the diffusion process. These results have shown that magnetic field acts principally on the branching growth but does not modify the crystal habit.