Bidirectionally Frozen Carbon Aerogel Reinforced by Tetrapod ZnO Bridges for High-Performance Pressure Sensing

Owing to the modulus mismatch between the supports and carbon layers, applied stress is preferentially concentrated at predefined “layer-support” interfaces, generating localized high-stress regions. Consequently, small mechanical stimuli induce pronounced resistance variations, transforming stress into a geometrically controllable and functionally amplified signal carrier. To enhance device durability, polydimethylsiloxane (PDMS) impregnation is employed to form a conformal elastic constraint layer.

The resulting aerogel sensor exhibits a high gauge factor of 34.4, an ultrahigh sensitivity of 248.41 kPa⁻¹ over a broad pressure range (0–19 kPa), fast response and recovery times (24/69 ms), and stable operation over 5000 loading–unloading cycles. The sensor reliably detects physiological signals and joint motions, demonstrating its potential for wearable and intelligent sensing applications. This work provides a scalable structural engineering strategy for improving the mechanical reliability and sensing performance of biomass-derived carbon aerogels.