Nacre-like composite is promising to realize the intriguing properties of graphene in metal matrix.
However, how to fabricate the composite with nacre-like structure and improve effectively its property is
still challenging. Here we report a facile synthesis of reduced graphene oxide(RGO)/copper(Cu) composite
with hierarchical layered structure based on molecular level mixing and self-assembly. The effects
of pH value, temperature, mixing method and graphene content on the microstructure and mechanical
property of composite were investigated. The pH value and temperature are the main factors in the
formation of hierarchical layered structure. For macroscale microstructure, the composites consist of
parallel carbon-rich strip aggregates and carbon-poor matrix. For microscale microstructure, the carbonrich
aggregate contains many micro-layered grains composing of alternating layers of graphene and
copper, forming a nacre-like composite structure. Furthermore, it is believed that the length-width ratio
of macroscopic aggregates related with the mixing method has a significant impact on the mechanical
properties of composites. The tensile strength of the 2.5 vol% RGO/Cu composite is as high as 748 MPa.
Moreover, good electrical conductivity is also obtained in the composites. This work provides a better
understanding of design graphene based composites with hierarchical layered structure and high
performance.