Mechanical energy harvesting: From piezoelectric effect to ferroelectric/ferroelastic switching
Wenbin Kang, Guosheng Ji, John E. Huber
Abstract
Mechanical energy harvesters show great potential as clean and sustainable energy sources to replace or supplement currently used chemical batteries . Conventional piezoelectric energy harvesting is constrained by low power density, which cannot generate sufficient electrical power for some electronics, particularly in space-sensitive applications. This review systematically examines the existing literature on piezoelectric energy harvesting , with an emphasis on the improvement of energy density by using different energy harvesting strategies. Then, attempts to use the non-linear electromechanical properties of ferroelectric/ferroelastic switching for energy harvesting are reviewed. Critical aspects of mechanical energy harvesting are covered: principles of energy conversion, operational modes, structure design, material properties, energy output, and applications. Comparing the piezoelectric effect to ferroelectric/ferroelastic switching, orders of magnitude increase in power density can be achieved by controlling polarization and residual stress. This review indicates that ferroelectric/ferroelastic switching could be a promising alternative to piezoelectrics for mechanical energy harvesting and identifies opportunities and future directions for practical applications.