Stretchable Heater with Entangled Vertically Aligned Carbon Nanotubes

In this study, we fabricated a stretchable heater composed of entangled vertically aligned carbon nanotubes (VACNTs) and a liquid metal (LM) electrode. Cross-linked VACNTs, which are electrically interconnected, can function as a heater through Joule heating. Notably, the VACNT bundles maintain electrical contact through the entanglement of strands even when tension is applied in the in-plane direction. By utilizing these characteristics, the proposed heater, which is fabricated by transferring VACNTs onto a stretchable substrate without a patterning process, has stretchability. As a result, the heater operates reliably even after being stretched repetitively for 300 cycles up to 50% of its original length. The proposed VACNTs-based stretchable heater is expected to find diverse applications in wearable haptic devices.