A Study Of Controlled Synthesis Of Gold Quantum Dots And Its Self Assembly

Gold quantum dots have unique optical, electrical, and magnetic properties, and havea wide range of applications and potential applications, it has been a research focus inthe field of nano materials. Nano electronic devices based on gold quantun dots hasalways been a hot topic and the accurate location of gold quantum dots is still a difficultissue.This paper centering around the problem has discussed controlled synthesis ofgold quantum dots and its optical properties and self assembly, and the followingstudies have been carried out:Size controlled synthesis of gold quantum dots. Gold quantum dots with different sizehave been synthesised by four kinds of method, including the reduction of gold chlorideacid by sodium borohydride, the reduction of AuPPh3Cl by TBAB, seed growthmethod and the reduction of gold chloride acid by Sodium Citrate. Gold quantum dotswith size of2-40nm have been obtained and in particularly gold quantum dots with sizeof2-10nm are uniformly synthesised. The precise size control of gold quantum dots hasbeen fulfilled and the advantages of different methods have been analysised.The characterization of gold quantum dots. The structure of Gold quantum dots ischaracterized by transmission electron microscope(TEM), scanning electron microscopy(SEM), X-ray diffraction(XRD). Various conditions which affect the quality of goldquantum dots, such as temperature, concentration of reductant, types of inclusions agenthave been discussed.The optical performance of gold quantum dots. The optical performance has beenanalysised by mie theory simulation and experimental tests with ultraviolet visiblespectrophotometer (UV-Vis). The experimental results and theoretical results arelearned in comparatively, which show that gold quantum dots have obvious quantumsize effect and small size effect, and that the position of absorbance peak has a blue shiftand its intensity is strengthened with the decrease of the size of quantum dots.The study of self-assembled gold quantum dots. Firstly dropping gold quantum dotson different bases, and it proved that gold quantum dots could be precisely located bythe leading of the structure of surface via simulations and experiments. Orderedmesoporous film has been synthesised, and the self assembly of gold quantum dots onordered mesoporous film has been processed, which is significant to the fabrication ofnano elctronic devices.