Cuttlebone-inspired lamella–pillar TEMPO-oxidized cellulose nanofiber/MXene hybrid aerogels with humidity-stable pressure-sensing performance

Abstract

Integrating rapid elastic recovery with humidity-resilient electrical functionality in cellulose-based aerogels remains challenging because interfacial instability and moisture-triggered degradation can jointly induce structural collapse and signal drift. Herein, lamella–pillar TOCNF/MXene/PMSQ composite aerogels with a conformal PMSQ-stabilized interface were constructed through a multiscale topology–interface engineering strategy. Directional freeze-casting generates an anisotropic lamella–pillar topology that facilitates reversible deformation and efficient stress redistribution, enabling high compressibility and rapid response/recovery behavior (163 ms/61 ms). The conformal encapsulation of a pre-hydrolyzed PMSQ network reinforces interfacial stability, imparts high hydrophobicity (142.45°), and mitigates humidity-induced electrical drift, while the interpenetrated TOCNF–MXene network maintains continuous three-dimensional conductive pathways. As a result, the aerogels exhibit durable cyclic stability (>8000 cycles) and high pressure sensitivity (235.2 kPa⁻¹) with humidity-resilient sensing outputs, enabling reliable physiological monitoring and human–machine interaction under humid conditions. This work highlights the coupling of topology-guided mechanics and interfacial stabilization as an effective strategy toward environmentally robust cellulose-based electronics.