Polymer-Passivated MXene Heaters for Ultrafast High-Temperature Heating and Autonomous De-Icing

Flexible electrothermal composites must combine high electrical conductivity, rapid thermal response, oxidation resistance, and thin-film processability. Two-dimensional transition metal carbides and nitrides (MXenes) are attractive conductive components because their high conductivity, electrothermal conversion efficiency, and solution processability enable ultrathin, conformable heaters. However, oxidation in ambient air disrupts interflake conductive pathways, forms titanium oxide phases, and causes resistance drift, limiting high-temperature operation. Here, we report a flexible polymer/MXene hybrid composite heater based on polymer-mediated interphase engineering. A surface-interacting polymer is conformally coated onto a Ti₃C₂T_x MXene film (T_x = -O, -OH, -F). Upon thermal treatment, the coating forms a polymer-derived interfacial network around interconnected flakes, suppressing oxygen attack while preserving continuous electron-transport pathways. The resulting composite maintains stable Joule heating in ambient air up to 500 °C, reaches a heating rate of approximately 336 °C s^-1, and exhibits stable electrothermal cycling under high-voltage operation. To demonstrate its practical applicability, the heater was evaluated in harsh-environment thermal-management applications. In an automotive electronic parking brake system, it increased the temperature of the EPB system from -30 °C to 10 °C within 60 s. Coupled with an artificial intelligence-based image-recognition model, it enabled closed-loop frost detection and autonomous defrosting of camera-cover glass within approximately 40 s, restoring optical clarity. This work establishes polymer-mediated interfacial passivation as a strategy for combining oxidation resistance, electrical continuity, and shape adaptability in composite heaters for on-demand de-icing and advanced thermal management