Facile decoration of two-dimensional Ti3C2Txnanoplates with CuS nanoparticles via a facilein situsynthesis strategy at room temperature for superhigh specific capacitance of supercapacitors.

Although supercapacitors have attracted more and more attention owing to their fast charging speed and high power density, their wide applications have still been limited by their low energy density. In this study, a new CuS-nanoparticle-decorated Ti3C2Txelectrode material is fabricated via a facilein situsynthesis strategy at room temperature. CuS nanoparticles, generated from thein situreaction of Cu (NO3)2·3H2O with Na2S·9H2O, are anchored between the Ti3C2Txinterlayers through electrostatic interaction. This type of structural construction is found capable of not only reducing the surface oxidation of Ti3C2Tx, but also preventing the accumulation of CuS nanoparticles by the template effect of Ti3C2Txnanoplates. As a result, the CuS/Ti3C2Txnanohybrid delivers a maximum specific capacitance of 911 F g-1at 1 A g-1and a good cycling stability. A symmetric supercapacitor fabricated using the CuS/Ti3C2Txnanohybrid as the electrode material exhibits an energy density of 43.56 W h kg-1with a power density of 475 W kg-1. Consequently, this work provides a new perspective of microstructural design for the preparation of electrode materials with superhigh specific capacitance through an easy and low-costin situ-reaction method at room temperature.