Green preparation of low-crystalline CoMoO 4 ·0.9H 2 O/carbon composite for energy storage applications using a mechanochemical method

Metal oxide/carbon composites have attracted considerable attention owing to their high charge storage capacity and excellent cycling stability. In this work, hierarchical porous carbon loaded with low-crystalline CoMoO4·0.9H2O (CMOC) was prepared via a solvent-free mechanochemical method. Due to the low-crystalline CoMoO4·0.9H2O, the porous structure, and the superior conductivity of carbon, CMOC exhibited good charge storage capacity (340 F g-1) and excellent cycling stability (~85% of capacitance retention for 10,000 cycles). Moreover, an asymmetric supercapacitor device (CMOC//AC ASC) was assembled using CMOC as the positive electrode and activated carbon as the negative electrode, thus achieving a high-energy density of 23.1 Wh kg-1 at a power density of 798.1 W kg-1. The mechanochemical method used in the study is simple, cost-effective, and generalizable. This study will provide valuable information for the large-scale preparation of metal oxide/carbon composites as electrode materials for supercapacitors.