Surface modification and Ag nanoparticles support of graphene nanoplates via plasma in liquid

Abstract

Graphene nanoplates (GNP) were modified via the plasma in liquid process (PLP) with two types of aqueous solutions for the fabrication of hydroxylated GNP and Ag-nanoparticles-physisorbed GNP. GNP were hydroxylated using the PLP in NaCl and hydroquinone aqueous solution. During the PLP employing AgNO3 aqueous solution, crystalized Ag nanoparticles with a diameter of around 10–100 nm were physisorbed on GNP with little functionalization. It was found that the amount of hydroxyl groups and Ag nanoparticles increased with the plasma treatment time.

Fabrication of polyrotaxane and graphene nanoplate composites with high thermal conductivities

“…[28] In contrast, our study features a lower content of Ag nanoparticles, approximately 10 wt% of the GNPs. [15] The synergistic enhancement of the thermal conductivity in the Ag/GNP composites due to the GNP and Ag nanoparticles was not observed along the in-plane direction; this might be because of the small amount of Ag nanoparticles physisorbed on GNPs and/or because the main heat conduction path was not along the GNP orientation.…”

“…The surface-modified GNPs were fabricated via PL in hydroquinone or silver nitrate aqueous solution (H-GNPs and Ag/GNP). Because the details of the modifications have been described in our previous report, [15] the preparation procedures are described briefly here. The GNPs were dispersed by a magnetic stirrer in a hydroquinone or silver nitrate aqueous solution at room temperature (20-25 C).…”

“…The solution was cooled in an ice bath to prevent overheating (the solution temperature was kept below 40 C). Each type of surface-modified GNP was separated by filtration, washed with ethanol, and dried overnight in an oven at 80 C. According to our previous study, [15] hydroxyl groups were mainly attached to H-GNPs and crystallized Ag nanoparticles with a diameter of approximately 10-100 nm were physisorbed on GNPs in Ag/GNPs.…”

“…[14] Furthermore, as with BN, CNFs, and CNTs, we has already demonstrated the surface modification of GNPs via the plasma in liquid (PL) process. [15] In this study, we fabricated PR composites filled with GNPs to achieve a higher thermal conductivity than those of previously fabricated PR composites. To observe the effect of the fabrication method on the composite's mechanical properties and conductivities, three types of surface-modified GNPs were prepared via the PL process.…”

“…To observe the effect of the fabrication method on the composite's mechanical properties and conductivities, three types of surface-modified GNPs were prepared via the PL process. [15] The mechanical properties and thermal and electrical conductivities of the GNP and PR composites were measured. For structural analysis, cross sections of the composites were observed using a field emission scanning electron microscope (FESEM).…”