Leaf-inspired flexible NFMs with multi-conductive network for multifunctional integrated physical sensing, joule heating, and noncontact thermosensation

The advancement of highly sensitive and multifunctional sensors is beneficial for promoting flexible electronic devices and human healthcare management. Herein, inspired by the bionic leaf structure, a flexible PVA-PEDOT: PSS/TPU-CNT@MXene nanofibrous membrane (PPTCM NFM) with a biomimetic interwoven pattern was constructed to manufacture multifunctional sensors and heating devices using advanced two-nozzle electrospinning and nano-welding technology. Because of the synergetic impact of the interwoven multi-conductive structure among MXene, fragile PVA-PEDOT: PSS (PVA-PP) network, and strong TPU-CNT network, which allowed the distribution of tensile load to each conductive layer, the PPTCM NFM displayed high sensitivity (the maximum gauge factor of 1132.8 at 55 %). Due to the slide of the MXene nanosheets and the stretching of PVA-PP, the PPTCM NFM exhibits fast response and recovery times of 780/780 ms at a low detection limit (1 % strain) and high dynamic response performance (500 mm min−1) under modest strains which enabled its utilization in monitoring both small human motions like facial expressions and throat vibrations. Nevertheless, the TPU-CNT layer provided support under large strains, allowing for the detection of larger-scale movements such as bending of fingers, wrists, elbows, and knees. In addition, the PPTCM NFM makes it easier for the mutual conversion of finger pressure and language. Notably, the PPTCM NFM also possessed outstanding Joule heating capabilities and electrical signal responsiveness to solar light radiation. This interconnected conductive network membrane served as a novel platform material for health monitoring systems and efficient personal thermal management applications.