MXene and MoS 3- x Coated 3D-Printed Hybrid Electrode for Solid-State Asymmetric Supercapacitor.

Recently, 2D nanomaterials such as transition metal carbides or nitrides (MXenes) and transition metal dichalcogenides (TMDs) have attracted ample attention in the field of energy storage devices specifically in supercapacitors (SCs) because of their high metallic conductivity, wide interlayer spacing, large surface area, and 2D layered structures. However, the low potential window (ΔV ≈ 0.6 V) of MXene e.g., Ti 3 C 2 T x limits the energy density of the SCs. Herein, asymmetric supercapacitors (ASCs) are fabricated by assembling the exfoliated Ti 3 C 2 T x (Ex-Ti 3 C 2 T x ) as the negative electrode and transition metal chalcogenide (MoS 3- x ) coated 3D-printed nanocarbon framework (MoS 3- x @3DnCF) as the positive electrode utilizing polyvinyl alcohol (PVA)/H 2 SO 4 gel electrolyte, which provides a wide ΔV of 1.6 V. The Ex-Ti 3 C 2 T x possesses wrinkled sheets which prevent the restacking of Ti 3 C 2 T x 2D layers. The MoS 3- x @3DnCF holds a porous structure and offers diffusion-controlled intercalated pseudocapacitance that enhances the overall capacitance. The 3D printing allows a facile fabrication of customized shaped MoS 3- x @3DnCF electrodes. Employing the advantages of the 3D-printing facilities, two different ASCs, such as sandwich- and interdigitated-configurations are fabricated. The customized ASCs provide excellent capacitive performance. Such ASCs combining the MXene and electroactive 3D-printed nanocarbon framework can be used as potential energy storage devices in modern electronics.