Flexible Ti3C2Tx MXene Film Coupled with Defect‐Rich MoO3 Spacer‐Contributor toward High‐Performance Wearable Energy Storage

Abstract MXene film‐derived flexible supercapacitors have shown great application foreground for wearable electronics, but the capacitive characteristics, especially when faced with mechanical deformations, are not satisfactory. Herein, a new kind of flexible electrode, MX/D‐MoO 3 , is developed by using Ti 3 C 2 T x MXene film (MX) and defect‐rich MoO 3 (D‐MoO 3 ) as the “main body” and “spacer‐contributor”, respectively. Results indicate that, with D‐MoO 3 intercalation, notably enlarged layer spacing of Ti 3 C 2 T x nanosheets and boosted electrochemical active sites are fulfilled, which have facilitated wondrous property increases of 342% and 239% when compared to raw MX and MX/MoO 3 , respectively. Particularly, MX/D‐MoO 3 ‐60 has a high specific capacitance of 2734.3 mF cm −2 at 1 mA cm −2 , which surpasses most of the counterparts reported thus far. The MX/D‐MoO 3 ‐60‐based all‐solid‐state supercapacitor presents the largest energy density of 96.3 µWh cm −2 at 205.9 µW cm −2 and an outstanding power density of 1871.4 µW cm −2 at 18.6 µWh cm −2 . Meanwhile, impressive stability with capacitance retention of 91.8% after 5 000 cycles and great mechanical flexibility with capacitance retention of 90.3% under bending angles from 0 to 180° are also exhibited. The superior properties and facile preparation endow MX/D‐MoO 3 ‐60 with promising applications in wearable energy storage.