Boosting the volumetric capacitance of MoO3-x free-standing films with Ti3C2 MXene

The high theoretical capacitance of molybdenum trioxide (MoO3) renders it an attractive supercapacitor electrode material. However, its low electronic conductivity restricts charge transfer and slows reaction kinetics. Herein, we vacuum filtered porous, free-standing, flexible highly conductive films comprised oxygen vacancy-rich MoO3-x nanobelts delaminated Ti3C2 MXene in a mass ratio 80:20, respectively. When tested as electrodes, 5 M LiCl electrolyte, volumetric capacitances 631 F cm?3 at 1 A g?1, 474 10 g?1 were obtained. To increase the energy density, asymmetric supercapacitors, wherein anodes MoO3-based cathodes nitrogen-doped activated carbon assembled tested. resulting density was 48.6 Wh L?1. After 20,000 continuous charge/discharge cycles 20 96.3 % initial remained. These values are outstanding for free-standing especially aqueous electrolytes.