Fabrication And Properties Of RGO/Cu Composites By PAS

Graphene/Copper composites has been widely used in machinery, electronic andenergy fields, due to its highly electrical conductivity, thermal conductivity andprocessing formability of Cu and fascinating electrical conductivity, thermalconductivity and mechanical strength of graphene. However, there has two maindifficulties to prepared the RGO/Cu composite, firstly, the graphene sheets sufferfrom very limited dispersibility and even irreversible agglomeration in the solvent,secondly, the poor wettability between RGO and Cu in the composite. To solve thisproblem, this paper fabrication of Cu@RGO powders with high dispersion RGOnanosheets were decorated by homogeneous Cu nanoparticles. Then the RGO/Cucomposites were prepared by PAS sintering, research on the sintering process,structure and properties of RGO/Cu composites.Firstly, graphene oxide (GO) and RGO/SnO2with the SnO2nanocrystal aresupport on the RGO nanosheets were prepared, the GO and RGO/SnO2wascharacterized by XRD, FESEM, TEM, FTIR and Raman, the results show that theGO dispersion in the aqueous solution, and GO was reduced to RGO after thereaction, the reduction of graphene oxide was homogeneously decorated with the insitu formation of SnO2nanocrystals with a size of2-3nm. The concentration of Vc,NaBH4, Vc+NaBH4and CuCl2can affect the microstructure of Cu@RGO powder.The optimized concentration to prepared the Cu@RGOpowder is: concentration ofVc0.15mol/L, concentration of NaBH4is0.01mol/L and the concentration of CuCl2is0.004mol/L, under this concentration, the Cu@RGO powder with homogeneousCu nanoparticles(about5nm) decorated on the highly disperse RGO nanosheets canbe prepared. Then, the Cu2O of Cu@RGO powder can be reduced to Cu under thehigh temperature H2atmosphere furnace.Secondly, the RGO/Cu composite were prepared by PAS. The sintering processcan influence the relatively density, at optimized sintering process of900℃-40MPa-10min, the relative density of RGO/Cu composite can achieved98.6%.Moreover, different content of Cu@RGO powder in composite can influence therelative density of RGO/Cu composite. The results showed that with the increase ofcontent of Cu@RGO powder, the relative density of RGO/Cu composites was decreased. The characterized results show that the RGO homogeneous dispersion inthe Cu matrix and closely connection with the Cu matrix.Finally, the electrical conductivity, thermal conductivity and compress yieldstrength of RGO/Cu composites was test. The results show that the electricalconductivity and thermal conductivity were decrease from57.5MS/m to55.2MS/mand from400.39w.m-1.k-1to370.54w.m-1.k-1with the increase of content of RGO/Cupowder, while the compress yield strength increases from257.52MPa to288.81MPaas the content of RGO/Cu powder increases.