Electrodeposition Of CdO Nanostructural Material

The unique properties of the nanostructure material make it different from the conventional materials, It has special physical and chemical characteristics. In this thesis, we fabricated CdO wire and film nanostructural material, and studied the mechanism of the deposit appearance.CdO is an n-type semiconductor with a direct band gap of about 2.5 eV and an indirect band gap of 1.98 eV. For its specific optical, electrical properties and high light transmittance in the visible region of solar spectrum, it has promising application in many fields such as solar cell, photo transistors, transparent electrodes and catalysts. CdO is also one of the most important sensor materials, it has a low ohmic resistance, the high reliability in harsh conditions, especially its selectivity towards liquefied petroleum gas (LPG), making it an excellent material in the detection of liquefied petroleum gas. It has great application value in semiconductor industry. For cadmium easily react with oxygen to form cadmium oxide when exposed in air, so most methods to fabricate cadmium oxide materials were prepare cadmium first, then performed the sample at certain temperature to oxidize it, lots of researches have down to diminish the temperature or to study the effect of the temperature. Another method is preparing the precursor Cd(OH)2 firstly,then heat it at certain temperature.In this experiment, we used nitric acid to adjust the pH firstly, by forming a single crystal ice, we constructed an ultrathin aqueous electrolyte layer between the ice and a SiO2/Si substrate according to the solute partition principle. By the optical microscope and the scanning electron microscope, the appearances were been represented, and its components and structures were analyzed by Electron Dispersion Spectrum and Transmission Electron Microscope. To the study of the directly fabricate CdO nanostructure material, we think the nitrate radical took part in the redox reaction, to afford oxygen to the reaction, and it also created a alkaline environment before the deposits. We explained the origin of the branch, it was caused by the high voltage we applied. We discussed the special structure that appeared on the wire and the film, we thought the concussion caused by the nitrate radical was the main reason, and we explained the reason that the direction of the nanosheets be perpendicular to the direction of electric field, the concentration gradient maybe was the main reason. At last, we studied the photoluminescence spectra of the sample.In conclusion, we fabricated the large scale area CdO wire and film nanostructure material by two-dimensional electrodeposition. It's amazing that we get CdO directly without the application of heat. So this method has great potential application for its simplicity and directness. We analyzed its appearance, components and structures, studied the photoluminescence spectra, found the source of the oxygen, analyzed and discussed the reason of the deposit appearance.