High areal capacitance of vanadium oxides intercalated Ti₃C₂ MXene for flexible supercapacitors with high mass...

Flexible all-solid-state supercapacitors (ASSSs) have caught the scientific attention to meet the explosive demand for portable and wearable electronic devices. However, it is difficult for flexible electrode materials to obtain a high areal capacitance at a high mass loading, which limits their commercial applications. In this study, vanadium oxide (V₂O₅) nanoparticles are introduced into Ti₃C₂ flakes with the aid of cetyltrimethylammonium bromide (CTAB). The intercalation of V₂O₅ particles in the interlayer of Ti₃C₂ establishes a hierarchical structure and facilitates the electrolyte penetration. As a result, the prepared CT-Ti₃C₂@V₂O₅ composite electrode achieves a high areal capacitance of 2065 mF cm^-2 at 3 mA cm^-2 and superior active mass loading (15 mg cm^-2). Meanwhile, over 93% capacitance is maintained after 6000 cycles at 18 mA cm^-2. The ASSS based on CT-Ti₃C₂@V₂O₅ delivers a high areal capacitance of 477 mF cm^-2 at 1 mV s^-1 and exhibits stable performance at different bending states, which reaches to the advanced level for the ASSSs based on MXenes.