부산대학교 도서관

Synthesized spherical nano metal particles produced in aqueous solution have applications in printing technologies. However, an alternate method for achieving a percolation threshold is to mix the spherical shape of the particles and become net-shaped copper oxide with a minimum weight percent of particles. In this study, before reducing to copper metal, copper oxide was synthesized first without the chelating agent for achieving a net shape and copper metal nano particles were synthesized with the chelating agent, bypassing the process of creating copper oxide. Potassium sodium tartrate was the chelating agent used to control the shape of copper metal nano particles in an alkaline solution. Various concentrations of potassium sodium tartrate changed the shape of these particles from web-like at low concentrations to needlelike and more spherical at higher concentrations. Potassium sodium tartrate restrained the coordination bonds around the metal particles, controlling the shape to be more spherical. Altering the pH in absence of potassium sodium tartrate changed the conditions for the formation of particles according to the Eh-pH diagram for copper, forming net-shaped copper oxide particles when the pH was 12-13 and a cubic shape when the pH was 5-6. The composition of the nano particles in both cases was confirmed using examination by XRD. These shapes have the potential to possess favorable electrical and thermal properties as predicted by bond percolation and the percolation theory.