Spider web-inspired multifunctional aerogel sensor: MWCNT/MXene/TOCNF synergize to achieve high-sensitivity multiple detection of humidity, pressure, and photothermal stimuli

In recent years, multifunctional sensors have garnered significant attention for various applications, including wearable devices and electronic skins. However, achieving high-precision measurements of multiple stimuli within a single device remains a challenge. Inspired by the functional hierarchy of spider webs, which feature radial and spiral networks, as well as a glycoprotein coating, we developed a multifunctional aerogel sensor based on a biomimetic design. The aerogel skeleton was fabricated by directional freeze-drying of TEMPO oxidized cellulose nanofibers (TOCNF) and MXene composites, yielding axially aligned pores that mimic the effective transport pathways of radial and spiral networks. Furthermore, a hydrophilic layer of carboxylated multi-walled carbon nanotube (MWCNT-COOH) was subsequently spray-coated on to the surface, forming a glycoprotein coating-like interface. The multifunctional MWCNT/MXene/TOCNF aerogel (MMTA) sensor demonstrates ultrasensitive detection capabilities for humidity, pressure, and photothermal stimuli, showing outstanding sensitivity values (14.35 %RH −1 , −10.51 kPa −1 , −10.53 °C −1 ) over wide detection ranges (11–97 %RH, 0.5–100 kPa, 24 °C–40 °C). This biomimetic approach of translating key structural and functional elements of spider webs into advanced sensor performance demonstrates the effectiveness of nature-inspired design for multifunctional sensing platforms.