High-Performance Textile Piezoresistive Sensor: Graded Contact Hollow Architecture with Synergistic Flame Retardancy, Superhydrophobicity, and Thermal Insulation.

To address the challenges of complex fabrication, low sensitivity under high pressure, and poor environmental tolerance in conventional textile pressure sensors, this study proposes an economical and effective graded contact hollow architecture sensor (CCHD) design. Through a multistage contact mechanism combining hollow cavities with gradient conductive carbon layers, the sensor's maximum sensitivity response range extends to 5 times (0-13.9 kPa, with a sensitivity of 4.30 kPa) that of traditional single-layer designs while achieving rapid 79/80 ms response and 4600 cycle stability. Combined with dodecyltrimethoxysilane and phosphoric acid flame-retardant synergistic modification, the sensor device also exhibits superhydrophobicity (WCA = 153.5°), self-extinguishing flame properties, and thermal insulation. It enables precise monitoring of full-scale physiological signals from respiration to limb movement while maintaining signal stability under extreme conditions including acid/base corrosion, liquid impact, and flame exposure. This intelligent textile integrating triple protection with sensing capabilities provides a simple solution for wearable devices in demanding scenarios such as medical monitoring, underwater exploration, and disaster rescue operations.