Contact–separation mode triboelectric nanogenerator utilizing carbon-fiber composite structure for harvesting mechanical energy

The rapid depletion and adverse environmental impacts of fossil fuels necessitate the development of alternative sources of sustainable and ecofriendly energy to address the increasing energy demand due to population growth and technological advancement. Energy harvesting is a major strategy for the generation of sustainable and clean energy. It involves the scavenging and subsequent conversion of the energy from the surroundings into usable electrical energy. In this study, the conversion of the mechanical energy externally applied to a carbon-fiber-reinforced plastic (CFRP)-based structure into electrical energy using a triboelectric nanogenerator (TENG) was demonstrated. CFRPs are ultralight composites with high strength and stiffness, and they are primarily utilized in aircraft and automobiles. CFRP was the primary component of the CFRP-based TENG (CFRP-TENG) developed in this study. The carbon fibers of the CFRP acted as an electrode. Polyamide 6, which corresponded to the matrix of the CFRP, and polytetrafluoroethylene, which was attached to the surface of the CFRP, acted as friction pairs. The CFRP-TENG generated a voltage, short-circuit current, and power of up to 62 V, 7.76 μA, and 400 mW m−2, respectively, with an optimal external resistance of 20 MΩ. A structural CFRP was successfully applied as a TENG in this study; thus, the possibility of transforming a CFRP-based structure into a self-powering structure was demonstrated. The technique used in this study is expected to serve as a novel approach for energy generation in cyber-physical systems. This will facilitate the attachment of self-supporting energy systems such as sensors, power management systems, and actuators to the human body without additional batteries.