서강대학교

초록/요약

Part 1. Preparation of copper hybrid conducting ink Copper nanoparticles of about 56 nm average size were prepared in aqueous solution by reducing copper ions in the solution (0.02 M) by hydrazine hydrate in the presence of cetyltrimethylammoniumbromide (CTAB) and polyvinylpyrrolydone (PVP) as stabilizers. The effect of copper nanoparticles incorporated into poly (3,4 ？ ethylenedioxythiophene) ？ poly(styrenesulfonate) (PEDOT/PSS) in the presence of CTAB and PVP as stabilizers in composite has been investigated. Part 2. Preparation of paste copper with copper nanoparticles prepared by electron beam irradiation Copper nanoparticles with narrow size of 5 ？ 7 nm were synthesized by using electron beam irradiation. The copper nanoparticles were stable in ambient air for three months. TGA showed that the copper nanoparticles prepared by using electron beam irradiation has the higher wt% of pure copper metal compared with the one prepared by chemical reduction using hydrazine hydrate (N2H4). The conductive copper paste with copper nanoparticles prepared by electron beam irradiation showed the higher conductivity than the paste with copper nanoparticles prepared by chemical reduction with N2H4 due to small size, less amount of surfactants on the surface and higher stability against the oxidation in ambient condition of copper nanoparticles prepared by electron beam irradiation. The highest conductivity of copper paste was determined as 170 S.cm-1 at 90 wt% of copper nanoparticles in the pastes. Part 3. Synthesis of Monodispersed Cadmium Sulfide (CdS) Monodispersed CdS particles were synthesized in different conditions. At low temperature, we could obtain monodispersed CdS nanoparticles without using surfactant. But at high temperature, the monodispersed CdS nanoparticles could be obtained when dispersing agent like PVP and gelatin were used. XRD patterns show that the cubic CdS was formed at low temperature and hexagonal CdS was formed at high temperature. TEM images and PL spectra show that all particles were cluster of small CdS crystals. Selected CdS particles were calcined at 500 oC to be cadmium oxide.