Ultrasensitive, Wide‐Range, and Durable All‐PET Piezoresistive Pressure Sensors Enabled by Carbon Aerogel Composite Engineering

Abstract

ABSTRACT Flexible pressure sensors are pivotal for smart healthcare and human‐machine interfaces, yet reconciling ultrahigh sensitivity, broad detection range, and robust durability remains a challenge. We propose a fatigue‑resistant piezoresistive sensor integrating a kind of carbon aerogel (CA)‑based sensing layers with copper interdigital electrodes on polyethylene terephthalate substrates. The sensing layer features a hierarchically rough surface and compressible percolated network, in which CA provides reversible porosity and asperities, multi‐walled carbon nanotubes toughen the scaffold and lower the percolation threshold; poly(3, 4‐ethylenedioxythiophene): polystyrene sulfonate serves as a conductive binder for interfacial anchoring. Three distinct sensing regimes are identified, dominated by interfacial contact, microparticle compression, and nanonetwork densification. The sensor achieves an ultrahigh sensitivity of 4126.4 kPa −1 and a broad detection range up to 500 kPa, overcoming the classic sensitivity‐ range trade‐off. It also exhibits excellent cyclic stability (20000 cycles at 100 kPa), benefiting from the interlocked sensing layer and all‑PET architecture with high mechanical flexibility, in contrast to conventional paper‐based or microstructured substrates prone to brittleness and fatigue. Moreover, the entire device is fabricated via a roll‑to‑roll‑compatible blade‑coating process, enabling scalable, low‑cost production. Real‑time physiological monitoring, pressure array recognition, and plantar pressure mapping demonstrate its promise for next‑generation wearable electronics and medical diagnostics.