▎ 摘　　要

In this study, a facile pyrolysis process is utilized to convert a mantis shrimp shell into a 3D bicontinuous porous, highly wrinkled, nitrogen-doped, graphene-like ultrathin carbon sheet (3D BWGC). The 3D BWGC achieves a high surface area of 2300 m(2) g(-1) and a pore volume of up to 1.63 cm(3) g(-1). The specific capacitance of the 3D BWGC in 0.5 M H2SO4 electrolyte is 370.9 F g(-1) at a current density of 1 A g(-1) and an operating voltage window of 1.1 V. By introducing Fe2+, the operating voltage window of 3D BWGC symmetric supercapacitors can reach 1.8 V in a neutral electrolyte, and a specific capacitance of 317.2 F g(-1) can be obtained at a current density of 0.5 A g(-1). Remarkably, the fabricated symmetric supercapacitors using 2 M MgSO4 + 0.05 M FeSO4 electrolyte demonstrated an energy density as high as 17.7 W h kg(-1) at a power density of 180 W kg(-1). The assembled supercapacitors exhibit good cycling performance, maintaining an initial capacitance of 87.2% over 30 000 cycles. These excellent performances indicate the promising prospects of 3D BWGC in high-performance electrochemical energy storage.