Fabrication of binder-free MXene/reduced graphene oxide/W18O49 film electrode for flexible supercapacitors

Abstract

MXene nanosheets tend to aggregate during operation, significantly impeding their utility. Yet, the defect can be validly solved by incorporating intercalation substances. Herein, binder-free MXene/reduced graphene oxide/W₁₈O₄₉ (MXene/rGO/W₁₈O₄₉) film is fabricated as supercapacitor electrode. W₁₈O₄₉ and rGO can foster the formation of interlayer structure with MXene nanosheets. This enlarging of interlamellar spacing facilitates establishing multidirectional ion transport routes and exposing more active sites. MXene/rGO/W₁₈O₄₉ manifests 581.2 F g⁻¹ specific capacitance at 1 A g⁻¹. Moreover, the assembled asymmetric supercapacitor (ASC), comprising of MXene/rGO/W₁₈O₄₉ and activated carbon (AC) as positive and negative electrodes, exhibits 1.6 V voltage window, along with 43.2 Wh kg⁻¹ energy density at 799.8 W kg⁻¹ power density. Notably, it retains 87.1 % capacitance after 10,000 cycles at 3 A g⁻¹. Optimization strategy for MXene/rGO/W₁₈O₄₉ film as electrode not only illustrates the viability of MXene advancement, but also offers significant technical backing for its utilization in the next generation of flexible devices.