(Invited) Synthesis of 3D Network Graphene Based on Physical Metallurgy

Abstract

As a new nanocarbon material with excellent mechanical, physical and chemical performances, graphene has been attracted wide attentions for the applications in many field, especially for the electrode materials of energy storage devices. The high quality, controllable and effective synthesis of GN are main issues for its application. A 3D network structural graphene is promising for increase the electrochemical properties. We report a synthesis strategy by combining chemical method with physical metallurgy，achieving high quality and effective synthesis of 3D network graphene from powder, sheet to bulk foam. Chemical vapor deposition, de-alloying and powder metallurgy methods have been successfully used for the synthesis. Furthermore, carbon nanotubes(CNTs) was introduced in the 3D graphene for increasing the strength and conductivity. The processes and effects of chemical and physical process on the graphene structure are introduced and investigated, and the performance of the 3D-GN as the electrode materials in supercapacitor and lithium ion battery are explored. Without any current collectors and binder employed, a lithium ion capacitor (LIC) was assembled by 3D graphene reinforced by CNTs, which can achieve a high active materials mass loading per area, a large operating voltage window (0.01-4.2 V), current density per area (> 3 mA cm-2) and comparable energy density per mass (32 Wh kg-1), as well as excellent long cycling performance. Therefore, the 3D graphene are expected to be ideal electrode materials in high-performance electrochemical energy storage devices.