Ultrafine Mo2C nanoparticles supported on three-dimensional hierarchical porous carbon architecture toward electrochemical energy storage applications

Abstract

A three-dimensional hierarchical porous carbon loaded ultrafine Mo2C (3DHPC-Mo2C) nanomaterial was synthesized by an effective approach that combines NaCl template and K2CO3 in-situ activation together. The 3D hierarchical porous carbon with macro-meso-micropores interlacing structure acts as a skeleton provides a large surface area (409 m2 g−1) and effectively prevents the agglomeration of Mo2C during the carbonization process, which not only conducive to expose more active sites and shorten the transmission path of electrolyte ions but also helps to give full play to the features of Mo2C, such as high conductivity. Because of the outstanding microstructure, the 3DHPC-Mo2C shows a superior electrochemical performance that delivers a high specific capacitance of 206 F g−1 at 0.5 A g−1 and superior cycling stability of 96.6% through 7000 cycles. Meanwhile, an asymmetric supercapacitor (3DHPC-Mo2C//AC) was assembled in ionic liquid electrolyte (EMIMAC/AN) and achieves a high specific energy of 20 Wh Kg−1 at the specific power of 224 W Kg−1, which is higher than most reported carbide-based asymmetric supercapacitors and provide a promising strategy for the preparation of Mo2C and its application in energy storage.