Laser-Textured Superhydrophobic Wearable Strain Sensors of L-CNT@PDMS with Superior Anti/Deicing Properties

Flexible sensors have outperformed traditional rigid sensors in healthcare and sports monitoring due to their flexibility and comfortableness. However, wearable sensors are susceptible to signal interference and external corrosion, leading to early failure of sensing performance. Inspired by the self-cleaning property of the surface microstructure of lotus leaves, we have designed a superhydrophobic flexible sensor of L-CNT@PDMS by a template method and a laser direct writing technique. Single-walled carbon nanotubes (CNTs) were incorporated into poly(dimethylsiloxane) (PDMS) to prepare a CNT@PDMS elastomer. Then, microcolumn arrays were generated by picosecond laser ablation. The effects of laser power density and micropillar structural parameters on wettability and sensing properties were investigated. The prepared L-CNT@PDMS sensor showed excellent superhydrophobicity (CA > 151°, SA < 3°), mechanical strength (breaking elongation of 110% and breaking stress >18 MPa), anticorrosion properties, and good sensitivity (gauge factor of 267). Meanwhile, the L-CNT@PDMS sensor possessed superior photothermal/electrothermal properties, showing delayed icing and deicing effects. These laser-textured superhydrophobic flexible sensors of L-CNT@PDMS with comprehensive performance have great potential applications in healthcare, motion monitoring, and underwater equipment.