Design and synthesis of three-dimensional hierarchical ordered porous carbons for supercapacitors

Three-dimensional hierarchical ordered porous carbons (3D HOPCs) have been successfully prepared through templating method using silica sphere nano-array as a hard template, triblock copolymer P123 as a soft template and sucrose as a carbon source, and used as the electrode materials for supercapacitors. The structure, morphology and physicochemical properties of the as-prepared 3D HOPCs are characterized by nitrogen adsorption-desorption isotherm, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) tests, and cycle life measurements. The results show that the 3D HOPCs possess well-interconnected 3D hierarchical ordered porous structure. Especially, the 3D HOPC-80, of which the pore size is 4.01 nm, shows the specific surface area of 1182 m² g^-1 and a specific capacitance of 247 F g^-1 at the current density of 1 A g^-1. Besides, the supercapacitors based on 3D HOPCs exhibit excellent rate performance, high energy densities of 7.5 W h kg^-1 and 5.8 W h kg^-1 at the power densities of 500 W kg^-1 and 10000 W kg^-1, respectively. Moreover, the supercapacitors using 3D HOPCs as electrode materials hold high capacitance retentions over 91% even after 10000 cycles.