Graphene/phenolic resin-based porous carbon composites with improved conductivity prepared via in situ polymerization in graphene hydrogels

Three-dimensional (3D) graphene/phenolic resin-based porous carbon composites with enhanced conductivity were prepared by carbonizing 3D graphene/phenolic resin composites and potassium hydroxide activation. The 3D graphene/phenolic resin composites were prepared via phenolic resin in situ polymerization in graphene hydrogels to protect the structure of 3D graphene. The prepared porous carbon composites exhibit an improved graphitization degree and enhanced conductivity by introducing 3D graphene. As supercapacitor electrode material, the electrochemical performance of the composite electrode materials was better than that of porous carbon prepared by pure phenolic resin due to the improved conductivity. The 3D graphene/phenolic resin-based porous carbon composite shows a high specific capacitance of 215.3 F g−1 at 0.1 A g−1, good rate capability of 72.9% in the range of 0.1–5 A g−1 and excellent cycling stability (only 3.4% loss in specific capacitance after 5000 cycles). The method developed in this work would open up a new route to design and synthesize 3D graphene/porous carbon composites for a variety of applications like supercapacitors, catalysts and fuel cells.