Graphene Sterically-Wrapped textile piezoresistive Sensors: A spray coating path for synergistically advancing sensitivity and response range

Trade-off between a high sensitivity and a broad sensing range remains a persistent challenge for flexible pressure sensors. Not to suffer from this dilemma, a flexible textile piezoresistive sensor sterically-wrapped with graphene by spray coating is reported, which constructs enriched three-dimensional conductive networks from leather fabric's inherent fiber and pore structures, synergistically advancing the sensitivity and response range. Such a sensor renders bulky spatial deformation and augmented pressure-induced conducting paths, and hence affords an ultra-high sensitivity of 259.6 kPa−1(0–100 kPa) and an exceptional response range of up to 1 MPa. Besides, the graphene/textile sensor demonstrates outstanding durability (>12000 cycles). With these advantages, real-time monitoring of human physiological activities such as wrist pulses and throat swallowing is successfully achieved. Benefitting from the scalability of the spraying methodology, a large-size 45 × 45 cm2 sensing array with a 32 × 32 matrix is facilely fabricated to map the spatial pressure of human interactive behaviors for ergonomics. And smart insoles incorporating graphene/textile sensors can capture plantar pressure distribution and provide effective analysis for diverse static/dynamic movements of feet. Such spray-coated textile sensors could not only find potential applications in wearable electronics and intelligent robotics, but also open the possibility of monitoring complex heavy machinery and large-scale infrastructures.