Mechano-thermo-acoustic Multifunctional Sensor Based on an MXene/Silk Fibroin Aerogel

Traditional sensors often suffer from limited material properties, fixed structural configurations, and a lack of tunability and three-dimensional (3D) porous architectures necessary to meet the growing demands for multifunctionality, miniaturization, and seamless integration. Here, a flexible sensor based on a 3D MXene/silk fibroin (SF) aerogel to meet the demands for multifunctionality was prepared. Due to the high electrical conductivity and superior elasticity of the layered porous MXene/SF aerogel formed by a rapid gas foaming process, the sensor is capable of monitoring multimodal signals, including mechanical, thermal, and acoustic stimuli. The sensor achieves a high sensitivity (103.14 kPa^-1), a minimum detection limit (1.96 Pa), a fast response time/recovery time (110.92 ms/77.81 ms), and good cyclic stability (>10,000 cycles). In addition, the sensor exhibits excellent repeatability and recognition capability for temperature changes. More importantly, it effectively distinguishes sound signals from different languages, achieving a language recognition accuracy of 96.58% by machine learning recognition. This work provides insights and approaches that can provide inspiration for the future development of high-performance and multifunctional integrated flexible sensors.