Formation Of Needle-like Particles Research Articles

Electrodeposition and growth mechanism of SnSe thin films

Tin selenide (SnSe) thin films were electrochemically deposited onto Au(111) substrates from an aqueous solution containing SnCl2, Na2SeO3, and EDTA at room temperature (25°C). The electrochemical behaviors and the codeposition potentials of Sn and Se were explored by cyclic voltammetry. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and UV–vis absorption spectroscopy were employed to characterize the thin films. When the electrodeposition potential increased, the Se content in the films decreased. It was found that the stoichiometric SnSe thin films could be obtained at −0.50V. The as-deposited films were crystallized in the preferential orientation along the (111) plane. The morphologies of SnSe films could be changed from spherical grains to platelet-like particles as the deposition potential increases. The SEM investigations show that the film growth proceeds via nucleation, growth of film layer and formation of needle-like particles on the overlayer of the film. The optical absorption study showed the film has direct transition with band gap energy of 1.3eV.

ChemInform Abstract: Sonohydrolysis of In3+ Ions: Formation of Needlelike Particles of Indium Hydroxide.

This paper describes the formation and characterization of nanosize needle-shaped In(OH)3 particles. The In(OH)3 nanopowder was prepared via the sonication of an aqueous solution of InCl3 at room temperature and at 0 °C. At these temperatures, nonsonicated hydrolysis does not occur. The role of the ultrasound radiation and the mechanism of the reaction is discussed. The proposed mechanism is based on the sonohydrolysis of In(III) ions in the outer ring, and the liquid shell, of the collapsing bubble.