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

Abstract

Abstract In this work, gold nanoparticles (AuNPs) decorated Ti 3 C 2 T x nanosheets (MXene/AuNPs composite) are fabricated through a self-reduction reaction of Ti 3 C 2 T x nanosheets with HAuCl 4 aqueous solution. The obtained composite is characterized as AuNPs with the diameter of about 23 nm uniformly dispersing on Ti 3 C 2 T x 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 Ti 3 C 2 T x and 95% of cyclic stability after 10,000 cycles. Furthermore, MXene/AuNPs composite symmetric supercapacitor with filter paper as separator and H 2 SO 4 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.