Ti3C2Tx MXene-based (Cobalt–Vanadium) bimetallic sulfides 0D@2D heterostructure composite for asymmetric supercapacitor application

Abstract

2D MXenes are receiving a significant attention in the energy-storage sector, owing to their high surface redox reactivity, hydrophilicity, multi-layered sheet structure, and high conductivity. However, MXenes are subjected to sheets restacking which decrease the number of surface-active sites, and thus limits their capacity value. In this work, CoVS₂ NPs are in-situ grown over the Ti₃C₂T_× nanosheets using a facile hydrothermal technique. The insertion of the nanoparticles can reduce the restacking of the sheets and creating abundant active sites. As a cathode material for the (ASCs) application, the CoVS₂@MXene hybrid electrode achieves a high specific capacity value of 423 mAh g⁻¹ at 1 A g⁻¹, with an outstanding cycling stability of more than 93 % capacity retention after 5000 working cycles. Moreover, the obtained CoVS₂@MXene//VS₂@MXene ASC device provides a significant energy density of ∼57.78 W h kg⁻¹ at 832 W kg⁻¹ power density, and 90.3 % capacity retention. Such results indicate that the CoVS₂@MXene hybrid material offers excellent potential for future development of a new MXene-based supercapacitor devices.