In situ reduced MXene/AuNPs composite toward enhanced charging/discharging and specific capacitance

In this work, gold nanoparticles (AuNPs) decorated Ti3C2Tx nanosheets (MXene/AuNPs composite) are fabricated through a self-reduction reaction of Ti3C2Tx nanosheets with HAuCl4 aqueous solution. The obtained composite is characterized as AuNPs with the diameter of about 23 nm uniformly dispersing on Ti3C2Tx nanosheets without aggregation. The composite (MXene decorated on 4.8 wt% AuNPs) is further employed to construct supercapacitor for the first time with a higher specific capacitance of 278 F.g(-1) at 5 mV.s(-1) than that of pure Ti3C2Tx and 95% of cyclic stability after 10,000 cycles. Furthermore, MXene/AuNPs composite symmetric supercapacitor with filter paper as separator and H2SO4 as electrolyte, is assembled. The supercapacitor exhibits a high volumetric energy density of 8.82 Wh.L-1 at a power density of 264.6 W.L-1 and ultrafast-charging/discharging performance. It exhibits as a promising candidate applied in integrated and flexible supercapacitors.

Automated summary

In this work, gold nanoparticles (AuNPs) decorated Ti3C2Tx nanosheets (MXene/AuNPs composite) were successfully fabricated through self-reduction reaction. The obtained composite exhibited uniform dispersion of 23 nm AuNPs on Ti3C2Tx nanosheets, leading to a higher specific capacitance and cyclic stability in supercapacitor applications. The composite also showed promising potential as a candidate for integrated and flexible supercapacitors.