Preparation And Application Of High Conductive Metal Nanostructures And Their Printed Electronic Ink

High conductive metal nanostructures possessing unique physicochemicalproperties are identified as key materials in conductive inks for printed electronicstechnology. At present, commercial and the domestic and foreign literatures about Ag,Cu conductive ink have many issues as needing inert environment, environmentalpollution, higher resistivity and so on. In this paper, using organic coating mechanism,air-stable Ag, Cu and their hybrid nanostructures were synthesized under atmosphericconditions, XPS and FT-IR was used to establish their interface model,TG was usedto estimate their initial oxidation temperature. Based on Ag, Cu nanostructures, withgreen ink solvents, conductive patterns were prepared by direct writing on flexiblesubstrates using Pen-on-Paper method. The resistivity of air sintered pattern wastested by four-point to explore its application in printed electronics, main researchresults are as follows:(1) The preparation of Ag nanostructures and their application. Air-stable silvernanoparticles (NPs) with an average diameter of16nm were synthesized incetyltrimethylammonium bromide (CTAB) and polyvinylpyrrolidone (PVP) solutions.The reaction was performed at room temperature and the input of extra inert gas wasnot necessary. Ag plates were firstly produced by controlling reaction time with FeCl3as inducing agent and vitamin C as the reducing agent. Flexible and conductivepatterns produced by Ag nanostructures exibited low resistivity2.7μ cm aftersintering at160oC in Ar.(2) Nano-Ag ink was used for preparation of triboelectric nanogenerator (TENG).Flexible Ag electrode firstly produced by silver nano-ink as one electrode of TENG,which is a simple and easy process. The relationship between the conductivity of Agelectrode and the electric output performance of the TENG was build. When theresistivity of the Ag electrode is6.6μ cm, the instantaneous output voltage andcurrent density of TENG can reach as high as160V and6.6μA/cm2.(3) With PVP and CTAB as the sole coating agent, Cu NPs were obtained bychontrolling the moral ratios of hydrazine to Cu salts with PVP or using tri-sodiumcitrate as initial reducing-cum-surfactant agent followed by hydrazine as a secondmassive reducing agent with CTAB as extra surfactant agent. These Cu NPs of14.03nm and12.35nm respectively in diameter has some aggregation with initial oxidatio temperature at135oC. After sintering in Ar at160oC for2h, the resistivity ofdrawn Cu patterns were achieved to13.4±0.4μ cm and7.2±0.6μ cm,respectively.(4) The preparation of PVP/CTAB-Cu nanoparticles (NPs) using PVP andCTAB as a mixed capping agent were systematically studied. The coating mechanismwas explored to establish their interface model. The Cu NPs of~6.5nm in diameterwere uniform, dispersion and the initial oxidation temperature up to165oC. Theresistivity of Cu patterns sintered at160oC for2h under ambient conditions was11±0.8μ cm.(5)1Cu2Ag mixed structures was prepared by Cu mechanically mixed with AgNPs. Using sintering and hot pressing sintering, the microstructure of conductivepattern was dense and the resistivity was achieved to6.8μ cm. In addition, thevitamin C and glucose as co-reductant, adding excess silver salt, were used to prepareCu-Ag core-shell structures with silver particles. Using injection method, theconductive pattern’s microstructure was dense and its resistivity was5.6μ cm.