Heaters for wearable electronic devices need materials with a high conductivity, transparency, mechanical reliability, and flexibility. Two-dimensional materials such as MXenes could fulfill these requirements. MXenes are thin layers of transition-metal carbides, nitrides, or carbonitrides.

Chong Min Koo, Korea Institute of Science and Technology (KIST), Seoul, Cheolmin Park, Yonsei University, Seoul, Korea, and colleagues have developed a flexible and sewable MXene thin-film heater. To create the MXene heater, the researchers first prepared titanium-carbide-based MXene flakes using a minimally invasive delamination (MILD) method with a Ti₃C₂ precursor solution. The MXene flakes were then coated onto polyethylene terephthalate (PET) fibers using wet chemical methods. The coated fibers were then sewed or knitted into textiles to create the heater.

The thin-film heater has an optical transparency of over 65 %, a low sheet resistance, a fast electrothermal response, a high intrinsic electronic conductivity, and a high mechanical flexibility (up to 180° bending). The heater could be integrated into a diverse range of substrates using conventional sewing and weaving processes.

• Shape-Adaptable 2D Titanium Carbide (MXene) Heater,
  Tae Hyun Park, Seunggun Yu, Min Koo, Hyerim Kim, Eui Hyuk Kim, Jung-Eun Park, Byeori Ok, Byeonggwan Kim, Sung Hyun Noh, Chanho Park, Eunkyoung Kim, Chong Min Koo, Cheolmin Park,
  ACS Nano 2019.
  https://doi.org/10.1021/acsnano.9b01602