▎ 摘　　要

The development of high capacitance, high rate capability, and stability compounded electrochemical energy storage devices is an important factor that is required to meet the challenge of energy depletion. In this work, a novel graphene-decorated 2D Ti3C2TX/polyaniline (GTP) nanocomposite was successfully fabricated by means of insitu oxidation copolymerization of aniline monomers on the surface of Ti3C2TX nanosheets with the decoration of small-sized chemical-vapor-deposited graphene nanosheets. The GTP nanocomposite shows promoted pseudocapacitive when used as a supercapacitor electrode, because the small-sized graphene can effectively prevent aggregation of the Ti3C2TX monolayers and facilitate the uniform growth of polyaniline on the layered structural Ti3C2TX. Furthermore, the small-sized graphene provides more ion/electrons transfer pathways, which acts like conductive bridges between the electrodes and the electrolyte. After assembling an asymmetric supercapacitor (ASC) device using GTP as the positive electrode and Ti3C2TX as the negative electrode, the device can operate in a voltage window up to 1.5V in 1M H2SO4. Most importantly, the GTP//Ti3C2TX ASC shows an outstanding electrochemical performance compared to the reported Ti3C2TX-based devices.