1. TEM images of MXene flakes aged for (a, c) 7 d and (b, d) 30 d^[29]

2. Diagram of the four main printing technologies for MXene ink

3. Relationship between throughput, ink viscosity and resolution provided for the four major printing methods

4. Schematic illustration of direct MXene ink printing^[38]

5. Milestone of the origin and development of MXene ink^{[29,37⇓ -39,52]}

6. (a) Schematic illustration of room-temperature direct printing of additive-free MXene inks for flexible wireless electronics; (b) Mechanism and (c) optical image of flexible MXene RFID temperature tag; (d) MXene RFID sensors to monitor surface temperature; (e) Fabrication of MXene NFC tags and (f) examples of application^[53]