Pore Size‐Engineered Three‐Dimensional Ordered Mesoporous Carbons with Improved Electrochemical Performance for Supercapacitor and Lithium‐ion Battery Applications

Abstract Three‐dimensional ordered mesoporous carbons (OMCs) are desirable for high performing energy storage devices because they provide a continuous electron pathway to ensure good electrical contact and also facilitate electrolyte ion transport by reducing diffusion lengths during charge‐discharge process. Here, we report the synthesis of three dimensional mesoporous carbon (CMK‐8) using KIT‐6 and sucrose as silica template and carbon source, respectively. Initially, KIT‐6, synthesized at different hydrothermal temperature (100, 130 and 150 °C) is used as silica template to prepare OMCs with different pore diameter. The resulting OMCs were extensively characterized by SAXS, FE SEM, HR‐TEM, BET and Raman techniques. The SAXS pattern shows distinct reflections at low 2θ range corresponds to ordered mesoporous structure of cubic Ia3d space group. The OMC possesses a specific surface area of 1017 m 2 /g with a mean pore size of 4.1 nm and large pore volume of 1.14 cm 3 g −1 . As electrode material for supercapacitor application, the resulting mesoporous carbon delivers a high capacitance of 252 F/g @ 0.5 A/g and shows good rate performance (75% retention in capacitance at high current rates) and outstanding cyclic stability (91% retention after 30,000 cycles). Further, as anode for Li‐ion battery application, it also exhibits promising specific capacity (856 mAh/g) with good cyclic and rate capability. The excellent electrochemical properties of the mesoporous carbon material are attributed to its three dimensional porous structure and high surface area with interconnected mesopores that provides rapid ion and electron transport during electrochemical process.