Development Trend of Nonlinear Piezoelectric Energy Harvesters

Due to the imperative development of vibrational energy utilization in wireless sensing, power supply for microdevices, energy storage, etc., energy harvesters and their efficiency are highly regarded by researchers. With the introduction of nonlinearity, the shortcomings such as narrow working frequency range, low power output, and high start-up threshold from linear energy harvesters were significantly improved and aroused a great increase in applications. In a broad sense, we usually classify energy harvesters as piezoelectric energy harvesters (PEH) and non-piezoelectric energy harvesters, which can be further classified into electromagnetic, triboelectric, and electrostatic energy harvesters. The development of energy harvesters with nonlinearity from the most cited literature in recent years and the trends have been reviewed in this paper. Systematic theoretical study, research of energy-harvesting materials, new methods for efficiency enhancement, circuits, and specific applications with energy harvesters have also been summarized and discussed for electromagnetic waves. This paper provides a brief reference for relevant scholars to understand the current development status, and trends of energy harvesters with nonlinearity.