Ti₃C₂T_<i>x</i> MXene-Reduced\nGraphene Oxide Composite Electrodes for Stretchable\nSupercapacitors

Abstract

The development of\nstretchable electronics requires the invention\nof compatible high-performance power sources, such as stretchable\nsupercapacitors and batteries. In this work, two-dimensional (2D)\ntitanium carbide (Ti₃C₂T_<i>x</i>) MXene is being explored for flexible and printed energy storage\ndevices by fabrication of a robust, stretchable high-performance supercapacitor\nwith reduced graphene oxide (RGO) to create a composite electrode.\nThe Ti₃C₂T_<i>x</i>/RGO\ncomposite electrode combines the superior electrochemical and mechanical\nproperties of Ti₃C₂T_<i>x</i> and the mechanical robustness of RGO resulting from strong nanosheet\ninteractions, larger nanoflake size, and mechanical flexibility. It\nis found that the Ti₃C₂T_<i>x</i>/RGO composite electrodes with 50 wt % RGO incorporated prove\nto mitigate cracks generated under large strains. The composite electrodes\nexhibit a large capacitance of 49 mF/cm² (∼490 F/cm³ and ∼140 F/g) and good electrochemical and mechanical\nstability when subjected to cyclic uniaxial (300%) or biaxial (200%\n× 200%) strains. The as-assembled symmetric supercapacitor demonstrates\na specific capacitance of 18.6 mF/cm² (∼90 F/cm³ and ∼29 F/g) and a stretchability of up to 300%. The\ndeveloped approach offers an alternative strategy to fabricate stretchable\nMXene-based energy storage devices and can be extended to other members\nof the large MXene family.