1. SEM images of sandwich-like Ti₃C₂T_x/CNT layers^[55]

2. Surface SEM images of the Ti₃C₂T_x/CNT film at various stretching states during the first strain-release cycle^[55]

3. (a) Schematic of the fabrication process for the bioinspired Ti₃C₂T_x-AgNW-PDA/Ni²⁺ sensor fabricated through the screen-printing method; (b) Schematic illustration of the structures for the “brick” materials (Ti₃C₂T_x and AgNWs) and “mortar” material (PDA/Ni²⁺); (c) Schematic illustration of the Ti₃C₂T_x-AgNW-PDA/Ni²⁺ sensor based on the “brick-and-mortar” architecture^[56]

4. Electromechanical properties of M-hydrogel composite and mechanisms Electrical response of M-hydrogel to (a) tensile strain and (b) compressive strain, with insets showing the corresponding GFs; Scanning electron microscopy (SEM) images of M-hydrogel surface (c) before and (d) after stretching; (e-f) Schematic illustration for the mechanism of the electromechanical responses from M-hydrogel^[58]

5. (a) Schematic diagram of the HF_{18 h}-d_{20 min}-Ti₃C₂T_x conductive film at various stretching states during the first stretching-releasing cycle. Top-view SEM images of (b) HF_{6 h}-d_{3 h}-Ti₃C₂T_x-, (c) TMA-Ti₃C₂T_x-, and (d) HF_{18 h}-d_{20 min}-Ti₃C₂T_x-based strain sensors in the maximum tensile state^[15]

6. (a) Working micromechanism and (b) the equivalent circuit diagram of MXene-material for piezoresistive sensor^[59]

7. (a) Schematic illustration of fabrication of MX/rGO aerogel, (b) fabrication of MX/rGO aerogel-based sensor and (c) the sensing mechanism^[60]

8. SEM images and schematic structures of (a) C-MX/CNC and (b) C-CNC; Schematic elasticity mechanisms of (c)C-MX/CNC and (d) C-CNC

9. Schematic illustrations of fabrication procedure of (a) MXene-sponge and (b-c) fabrication of MXene-Sponge/PVA NWs based sensor^[64]