Multifunctional Conductive Elastomeric Composites for Broadband Electromagnetic Radiation Shielding and Biomechanical Energy Harvesting

The demand for eco-friendly, tactile-integrated, multimodal sensors with self-powered and self-healing capabilities is rising, especially for autonomous sensing systems in smart homes, healthcare, and electronic skin applications. This research introduces multifunctional, self-healing nanocomposites exhibiting remarkable strain sensing, triboelectric nanogenerator (TENG) capabilities, and electromagnetic interference (EMI) shielding. These composites are synthesized by a two-step wet and melt mixing process, integrating zinc oxide cross-linked, 1-(3-aminopropyl) imidazole (API)-grafted carboxylated nitrile butadiene elastomer (XNBR) with multiwalled carbon nanotubes (MWCNTs) to establish a network that is continuous and conductive, resembling nacre. The materials exhibit a self-healing capability of 78.2% at 45 °C while preserving outstanding mechanical strength and elasticity. The composites exhibit an EMI shielding efficacy of −26.4 dB, an open-circuit voltage of ∼224 V, a short-circuit current of ∼24.9 μA, and a power density of 1.1 W/m2 at a load resistance of 5 MΩ. The material exhibits strain sensitivity with a gauge factor (GF) of 9.78 at elevated strain levels reaching 50%. Furthermore, they incorporate a reversible ionic network that facilitates self-healing properties with autonomous sensing, enhancing smart home, healthcare, and electronic skin technologies. The durability and multifunctionality provide valuable insights for the creation of elastomeric composites that are both high-performance and possess superior mechanical properties, strain sensing capabilities, EMI shielding, self-repair functions, and triboelectric nanogenerators for power portable electronic devices. These versatile and sustainable nanocomposites offer potential for wearable electronics, tactile sensors, and durable environmental solutions.