Self-powered and self-sensing devices based on piezoelectric energy harvesting

Wearable devices, interactive human-machine interface equipment, wireless sensors, and small-scale cleaning devices play crucial roles in biomedical implantation, disease treatment, health monitoring, environmental purification, etc. These devices require a sustainable energy source to work effectively. With the consideration of the global energy crisis and environmental pollution, researchers are exploring new, stable, and environmentally friendly methods to power these low-powered devices. Mechanical energy is one of the most abundant natural energy sources. Converting mechanical energy from the ambient environment or host structures into electrical energy via the direct piezoelectric effect is an efficient energy harvesting technique. This paper reviews the application of advanced piezoelectric materials, and small-scale self-powered and self-sensing piezoelectric devices at the cubic centimeter scale in energy harvesting and health monitoring of human, animal, machinery, roads, bridges, as well as the pollutant degradation of the environment. Some of these devices have the capability to not only harvest mechanical energy but also enable real-time monitoring and analysis of the electrical signals generated by the direct piezoelectric effect, facilitating prompt decision-making and appropriate responses. In addition, potential challenges and future prospects of small-scale self-powered and self-sensing piezoelectric devices are discussed.