Preparation And Application Of Graphene Conductive Inks

Conductive ink is a composite material composed of conductive materials and is the core material of modern printed electronics technology.Currently,the traditional printing field and modern nanotechnology has made the application of conductive inks more extensive,moving towards functionalization and intelligence.The conductive materials of conductive inks are mostly expensive metals and general high conductivity materials.These metal-based inks are either expensive or have problems such as performance degradation caused by oxidation,which are difficult to avoid and solve.Although carbon-based conductive inks are increasingly popular due to their advantages of low cost and environmental protection,the problem of low conductivity is the key constraint factor.Therefore,it is of great practical significance to develop carbon-based conductive inks with high conductivity.In view of this,we have prepared high-conductivity graphene by in-situ mechanical peeling method as the research target,aiming at the technical bottleneck of low conductivity of carbon-based conductive ink.Taking the preparation of graphene conductive ink as the core,using the dispersing ability and bonding ability of water-soluble polymer,the high concentration graphene aqueous dispersion is prepared by in-situ physical mechanical peeling method.And the bonding ability,the high-concentration water-soluble graphene solution is obtained by in-situ physical separation,and the conductive high-conductivity graphene conductive ink is obtained by formulating the conductive filler,thereby solving the low conductivity of the carbon-based conductive ink.Besides,we have conducted in-depth research on the flexibility,corrosion resistance and functionality of graphene conductive ink films,which provide ideas for the application of graphene conductive inks in flexible electronic devices.The main research contents are as follows:1.High-concentration,high-quality graphene aqueous solution was prepared by in-situ physical mechanical peeling method,and the relationship between stripping time and graphene solution concentration,graphene size and conductivity was investigated.Through the characterization of graphene solution stability,electrical conductivity and structure,it is proved that graphene with adjustable chip diameter,good stability,high conductivity and complete lattice structure is a high-quality conductive filler for preparing graphene conductive ink.2.Using a high concentration of graphene aqueous solution as a raw material,adding an auxiliary agent and blending to obtain a uniformly dispersed graphene conductive ink.Graphene conductive inks form desired patterns on substrates of different surface properties and types,and have good adhesion.The obtained graphene conductive film is subjected to a simple annealing treatment,and the decomposed polymer forms sufficient amorphous carbon and is wedge-shaped interposed between the two-dimensional graphene,thereby effectively forming a compact face-dot-face structure,which is extremely large.The film conductivity is improved and the conductivity is up to 754 S/cm.3.Graphene conductive ink is sprayed on different kinds of substrates to form a film.The film not only can resist acid and alkali and neutral environment,but also has good bending resistance;after the film is soaked for several minutes in different volume fractions of conductive synergist,the square is greatly reduced;the graphene ink conductive circuit maintains a good conductive path in the-180° folding and 180° folding and the LED chip on the three-dimensional circuit board under folding.Finally,the graphene conductive ink film exhibits excellent electrothermal conversion performance and heat cycle performance under pressure.