High-Performance Bimodal Temperature/Pressure Tactile Sensor Based on Lamellar CNT/MXene/Cellulose Nanofibers Aerogel with Enhanced Multifunctionality

Abstract

The rapid development of thermoelectric-piezoresistive dual-mode sensors has opened new avenues for enhancing the functionality, miniaturization, and integration of flexible tactile sensors. However, existing research primarily focuses on decoupling temperature and pressure responses, which leaves a significant gap in optimizing sensor performance and exploring multifunctional applications. To address this limitation, a composite aerogel with a layered porous structure is developed, integrating carbon nanotubes and MXene as conductive materials and reinforced with cellulose nanofibers. The innovative design, characterized by ultra-low thermal conductivity along with superior electrical and thermoelectric properties, allows the resulting sensor to monitor temperature and pressure stimuli without interference through thermoelectric and piezoresistive mechanisms. Demonstrated results reveal exceptional sensing capabilities, including a minimum detectable temperature variation of 0.03 K and a pressure detection limit of 0.3 Pa. The sensor exhibits high sensitivities of 33.5 µV K⁻¹ and −45.2% kPa⁻¹, along with stability across both temperature and pressure stimuli. Furthermore, the unique multi-modal sensing mechanism supports various applications, such as thermoelectric energy harvesting, material recognition, complex information transmission, smart wearable devices, electronic skin, and human-computer interaction interfaces. This research presents a robust solution for designing high-performance dual-modal tactile sensors and significantly advances their practical applications across multiple domains.