Formation of air-stable copper nanoparticles for inkjet printing

Glavni cilj nanotehnologije je formiranje uzoraka materijala s potpuno novim i drugačijim svojstvima u odnosu na uzorke u makro obliku. Istraživanja u području sinteze nanočestica metala vrlo su zanimljiva sa znanstvenog i industrijskog aspekta. Predmet istraživanja ovog diplomskog rada je priprema nanočestica bakra stabilnih na zraku i pogodnih za ispis uporabom tintnog pisača. Nanočestice bakra sintetizirane su metodom kemijske redukcije iz vodene otopine, uporabom različitih prekursora i redukcijskih sredstava. Prekursori koji su korišteni su soli Cu(Ac)2, Cu(NO3)2 i Cu(SO4)2, te dva redukcijska sredstva N2H4 i NaBH4. Površina nanočestica bakra zaštićena je slojem elementarnog srebra kako bi se spriječila oksidacija bakra u procesu sinteriranja. Uvjeti sinteze sistematski su mijenjani kako bi se provjerio njihov utjecaj na veličinu nastalih nanočestica i na kinetiku kemijske reakcije. Nastale nanočestice karakterizirane su primjenom UV-Vis spektrofotometrije i cikličke voltametrije.The main objective of nanotechnology is the formation of materials with different, novel properties compared to their macro-sized counterparts. During the last decade, synthetic methods for the preparation of metallic nanoparticles represent one of the most investigated research field. The main subject of research in this thesis is preparation of air-stable copper nanoparticles suitable for inkjet printing technology. Copper nanoparticles have been synthesized by the chemical reduction method from aqueous solutions, using different precursors and reducing agents. Different copper(II) saltes were used as a precursor specimens: acetate, nitrate and sulfate. Besides precursor molecule, two fast-kinetic inorganic compounds, N2H4 and NaBH4, were examined as the reducing agents. The surface of the copper nanoparticles was covered with metalic silver layer in order to protect grains from further oxidation during sintering process. Synthesis conditions are systematically modified to check their effects on the size of the formed nanoparticles and on the kinetics of chemical reactions. The resulting nanoparticles were characterized by UV-Vis spectrophotometry and cyclic voltammetry