Integrated layered structure-enabled high interfacial compatibility for sensitive, self-healing flexible conductive composites

Recently, the layered structure in flexible conductive composites has attracted widespread interest owing to its potential to resolve the conflict between conductivity and self-healing performance. However, the flexible conductive composites equipped with layered structure still face the challenges of long self-healing time, low conductivity, and poor interface compatibility. Herein, we propose a strategy to address the above issues through an integrated layered structure where the oxidized natural rubber latex (oNRL)/sodium alginate (SA)/carbon nanotubes self-healing layer mixture permeates and seamlessly adheres to the oNRL/SA/silver nanowires (Ag NWs) layer, creating an integrated layered structure. The CNT and Ag NWs endow composites with excellent photothermal conversion performance (170 °C at 0.55 W/cm²) and ultrahigh conductivity (862 S/m), respectively. Meanwhile, the composites have no interface problems since the self-healing layer and conductive layer bonded together to be an integral structure during film-formation. The resultant composites have acceptable tensile strength of 2 MPa and stretchability up to 429 %, and excellent photothermal self-healing performance. The conductivity of composites after damage can be restored to 90.3 % at an irradiation of 0.37 W/cm² for 3 min. The composites also have fascinating ultra-sensitivity (GF ≈ 184.8) and good reliability, which make it applicable to human motion detection.