Fabrication of self-healing strain sensor based on AgNWs and Fe2O3 nanocomposite on engineered polyurethane substrate

Abstract

The development of flexible and self-healing electromechanical sensors has garnered increasing attention recently because of its numerous applications in various sectors. A simple, low-cost sandwich-structured strain sensor was made employing silver nanowires (AgNWs) and ferric oxide (Fe₂O₃) nanocomposite on an engineered Polyurethane (PU) substrate with good sensitivity, bendability, stretchability, and self-healing. With a GF of 42.84 at 30% of applied strain, the nanocomposite-based strain sensor PU/(AgNWs/Fe₂O₃)/PU is highly sensitive. Due to many factors, including the magnetic force of iron oxide healing the conductive layer and reverse hydrogen bonding healing the PU substrate, the fatigued PU/(AgNWs/Fe₂O₃)/PU nanocomposite film caused by repetitive cyclic loading can self-heal. Stretchability up to 30% and sensor recovery of 95% after cutting and healing, the constructed strain sensor displayed a stable response and restored its resistance to its original location. Additionally, the AgNWs/Fe₂O₃ nanocomposite strain sensor is stable and durable with 10,000 endurance cycles. With frequent finger bending and wrist movement, the current and resistance changed very regularly. The strain sensor PU/(AgNWs/Fe₂O₃)/PU can detect body actions and restrain physiological signals like finger and wrist joint movements due to its increased performance. Thus, the wearable sensor is expected to track human body mobility and detect physiological signals over time. Thus, these findings may aid the creation of self-healing wearable strain sensors and electrical gadgets.