Construction of CoMoO4 nanosheets arrays modified by Ti3C2Tx MXene and their enhanced charge storage performance for hybrid supercapacitor

Abstract

MXenes are considered to be a new two-dimensional material with excellent conductivity, large specific surface area, and fast transfer channels for electrons, thereby provides efficient bridge to improve conductivity and structural stability of battery-type electrode materials. In this work, Ti3C2Tx MXene is integrated into CoMoO4 nanoarrays by a simple hydrothermal process to form a cross-supported nanoarray structure of CoMoO4-Ti3C2Tx with three-dimensional heterogeneous interface. It is worth noting that CoMoO4 thinner nanosheets expose more electrochemical active sites under synergistic effect of Ti3C2Tx MXene, thereby greatly increases the specific capacity of CoMoO4 nanoarrays. At the same time, it can alleviate the volume expansion and contraction of CoMoO4 materials during the charge-discharge process, and thus improves their cycle life performance. The CoMoO4-Ti3C2Tx nanoarrays show a high specific capacity value of 870.7 C g−1 at a current density of 1 A g−1,and capacity retention rate of 68.2 % after 6000 cycles, which is better than the unmodified CoMoO4 electrode (specific capacity: 737.0 C g−1, retention rate: 54 % after 5000 cycles). Furthermore, a hybrid supercapacitor fabricated by CoMoO4-Ti3C2Tx and N-doped graphene electrode delivers high capacitance value of 148 F g−1 and energy density of 46.3 Wh kg−1. This work demonstrates great potential of the CoMoO4-Ti3C2Tx nanoarrays for high-performance supercapacitors.