Printable Hybrid Micro-Supercapacitor Based on 2-D Inks using Graphene, TMDs and M-Xenes

This project report outlines the design and preparation of 2D heterostructured nanocomposites for supercapacitor/micro-supercapacitor-relevant electrodes, focusing on vertically integrated architectures that combine Ti₃C₂Tₓ MXene, graphene, and MoS₂ to couple high conductivity with ion-accessible interfacial charge storage. The work establishes a synthesis workflow in which few-layer Ti₃C₂Tₓ (FLTx) dispersions with controlled areal size are produced via LiCl-assisted intercalation/delamination, followed by probe sonication (pulsed, temperature-controlled) and centrifugation-based fractionation. Using these FLTx building blocks, Ti₃C₂Tₓ–MoS₂ (TTxMS) is prepared by in situ hydrothermal growth of MoS₂ from soluble precursors in a Teflon-lined autoclave (200 °C, 24 h), followed by washing/drying and N₂ annealing at 500 °C to improve phase quality and interfacial coupling. In parallel, Ti₃C₂Tₓ–graphene (TTxGE) heterostructures are assembled by co-dispersing size-selected MXene with graphene nanoplatelets and applying controlled sonication/centrifugation to promote sheet-to-sheet contact while limiting restacking. Building on these steps, MXene–graphene–MoS₂ double heterostructures are obtained by introducing Mo/S precursors to the MXene–graphene scaffold and applying the same hydrothermal and post-treatment workflow, yielding a hierarchically stacked network designed to maximize interfacial area for charge transport and redox accessibility. A suite of complementary characterization methods is then used to verify composition, structure, and heterostructure formation. XPS shows the surface chemistries of FLTx, graphene, and the hybrids (including Mo and S in MoS₂-containing samples), and supports retention of MXene terminations/partial oxidation signatures in the composites. XRD indicates that the samples are predominantly composite/multiphase assemblies, with MXene low-angle reflections persisting after hybrid processing and additional contributions attributed to secondary phases arising from processing history. SEM reveals exfoliated sheet-like morphologies for few-layer MXene and increased surface roughness/decoration after MoS₂ integration, while EDX verifies the intended elemental incorporation (including Mo and S) within the MXene matrix. Raman spectroscopy provides vibrational confirmation of MoS₂ in the composites superimposed on the broadened MXene background, and UV–Vis–NIR shows broadband optical absorption (250–1100 nm) consistent with conductive MXene-dominated attenuation with composite-dependent variations in dispersion/interaction effects.