Electrochemical high-energy deposition of CdSe nanostructures: modelling, synthesis and characterization

Cadmium selenide nanostructures have been electrodeposited on Ti substrate from aqueous acidic solution under high-energy conditions produced by pulse potential technique employing -300 V deposition potential and 50 A mu s pulse width. The transport processes in non-steady state have been studied by mathematical modelling on the basis of the diffusion equation. The calculations have confirmed that the high-voltage pulse electrodeposition operates very high energy localized close to the electrode surface, and the limit of the CdSe formation zone was calculated to be 1 A mu m from the cathode surface. It has been demonstrated that the solution composition affects the deposit morphology through its effect on the local current density in the near-electrode layer. X-ray diffraction analysis showed as-deposited CdSe had zinc blende crystalline structure that changed to hexagonal after annealing. Local elemental analysis confirmed stoichiometric composition of as-deposited and annealed deposits. The optical band gap was found to be 1.64 eV from the absorbance spectra. [GRAPHICS] .