Graphitized hierarchically porous carbon nanosheets derived from bakelite induced by high-repetition picosecond laser

•Organic materials can be graphitized by high-repetition picosecond laser.•GHPCNs flakes with mesopores and macropores derived from bakelite was prepared.•GHPCNs flakes has in-plane lattice defects with pentagon-heptagon structures.•Porous structures and shapes of GHPCNs films can be controlled by laser parameters.•The methodology is a potential way of producing energy storage micro-devices.