Intercalating Ultrathin MoO3 Nanobelts into MXene Film with Ultrahigh Volumetric Capacitance and Excellent Deformation for High-Energy-Density Devices

All-pseudocapacitive and highly deformable MXene hybrid film is successfully fabricated by a facile and efficient vacuum-assisted filtration of ultrathin MoO 3 nanobelts and delaminated MXene nanosheets. The optimal M/MoO 3 hybrid electrode delivers an ultrahigh volumetric capacitance of 1817 F cm −3 (545 F g −1 ), which exceeds large majority of previously reported MXene-based flexible electrodes. The symmetric supercapacitor presents excellent energy density of 44.6 Wh L −1 (13.4 Wh kg −1 ), indicating the electrode promising in achieving high-energy-density devices.