Spider-web-structured CNTs/CuS coating-based flexible pressure sensor with extreme self-heating and anti-freezing ability as a safeguard for winter sports†

Abstract

Winter sports have gained popularity in recent years. These sports and activities, however, come with some health concerns, particularly in harsh and extremely cold conditions. A self-heating, flexible, and smart conductive material that can monitor body health in extreme conditions would thus be highly desirable. Inspired by the structure of a spider-web, a flexible pressure sensor was developed by depositing a CNTs/CuS composite coating on a fabric surface with a cellulose-entangled structure constructed by hydroxypropyl methyl cellulose (HPMC). The obtained flexible pressure sensor demonstrated stable physiological signal detection and temperature insensitivity during photothermal heating, attributed to the water-retention capacity of HPMC. In addition, it exhibited excellent electrical conductivity (resistance of 10 Ω cm⁻¹), deicing (181s), sterilization (≈99.99%), UV resistance (UPF ≈ 13 926), environmental adaptability (−78 °C to 50 °C) and high sensitivity (13.25 ± 0.123 kPa⁻¹). This coating process can be applied to various garments, offering new possibilities for designing and preparing wearable multifunctional sensors.