Preparation Of Cu-Ag Core-shell Nanoparticles And Their Application In Printed Circuits

With the continuous development of e-commerce,Internet of Things,smart home,wearable devices and cloud computing,the demand for electronic components will continue to increase.Mainstream electronic components are mainly manufactured using a photolithography process,which requires complicated processes,expensive equipment,high costs,and difficulty in large-scale,large-area flexible manufacturing.The printed electronics technology prints electronic inks with specific functions on substrates of different properties to make electronic components and circuits by traditional printing processes.The method is simple,the requirements of equipment is not high,and mass production can be achieved.Personalized production can be realized in low cost.There has been great development in many fields.In this paper,related studies have been conducted on conductive fillers in electronic printing conductive inks.By liquid-phase reduction methods,the uniform nanoparticles were prepared after constant attempts to adjust the amount of reducing agent,amount of dispersants,reaction temperature,and reaction time.The sphere-like 50~60nm copper nanoparticles were further subjected to displacement reaction to prepare copper-silver core-shell nanoparticles with the same size.Through the SEM,TEM,XRD,EDS,TG,XPS analysis and testing of the synthesized copper nanoparticles and copper-silver core-shell nanoparticles,the morphology and composition of the nanoparticles were determined.The latter was found to have stronger anti-oxidation,able to withstand 156.3 oC heating in air without being oxidized,stored in the air for 3 weeks,and only 16.7% of the surface layer was oxidized.Sintering performance is also more excellent,and sintering can be achieved at 200 oC.During the entire sintering process,the melting and fusion effects of copper and silver films are all more pronounced than pure copper films.Finally,the prepared copper-silver core-shell nanoparticles were used as conductive fillers,mixed with safe and harmless organic solvents,binders,dispersants,additives to make conductive inks for screen printing,and the complete circuit diagrams were printed on a flexible polyimide(PI)film,the lines with a line width of 0.5 mm and 0.3 mm can be printed clearly,and the printed patterns were sintered,and the conduction of the circuit was finally realized even when the circuit is bent to 180 o,the on-state remained unaffected,which provides the possibility of printing flexible circuits.