Preparation of surface coatings on a conductive substrate by controlled motion of graphene nanoflakes in a liquid medium

Abstract

Controlled motion of graphene and graphene oxide nanoflakes in a thin liquid film on metal surfaces was studied to unravel the significant variations of the electric field effects on the nanoparticles. It was found that graphene oxide flakes were negatively charged and migrated toward anode while the electrically neutral graphene flakes moved toward cathode. Therefore, thin layers of graphene as a protective coating were produced to inhibit corrosion of underlying metals and reduce friction and wear-related mechanical failures in moving mechanical systems. The method does not require an insulated substrate to confine the high electric field to the fluidic layer. The motion of the nano-particles under pulsed electric current was very efficient. The observed effects were interpreted in a possible mechanism associated to the effect of electric field on the mobility of different particles in different conductive media. This significant phenomenon, combined with unique properties of graphene and graphene oxides, represents an exciting platform for enabling diverse applications on the preparation of protective coatings on an arbitrary conductive substrate over large areas.

Electric-field-induced alignment of electrically neutral disk-like particles: modelling and calculation

“…It is found that direct current electric field drives multiwall carbon nanotubes move toward negative electrode and alternating current electric field can align the nanotubes in liquid solutions 12 . Our previous researches shown that electric field can drive spherical particles to move toward a wall from the inner position in liquid metal 19 and can drive graphene nanoflakes to move toward the negative electrode 20 . It is also demonstrated recently that electric field can help to breakup droplets into fine particles 21 and rotate crystals’ orientation 22 .…”

Study of microstructure and mechanical properties of friction stir welded ferrite-martensite DP700 steel

“…The aligned carbon nanotubes are desirable in the replacement of the damaged nerves in biological experiments [4]. The aligned graphene is desirable in surface coating [5]. Carbon nanotube is a rod-like geometry.…”