Abstract
Thermal energy conversion using non-linear pyroelectric materials present a sustainable solution for transforming waste heat into useful energy. By utilizing the temperature and electric field dependence of these materials, heat can be directly converted into electrical energy. This review explores non-linear pyroelectric energy conversion, highlighting the use of ferroelectric materials and their non-linear behaviour in thermal energy harvesting. In this work, we critically examine the materials, thermodynamic cycles for pyroelectric energy conversion, figures-of-merit for pyroelectric energy harvesting, and the influence of material geometry, aging and conversion losses. The primary objective of this review is to emphasize the importance of power generation through pyroelectric modules and re-examine the scope of macroscopic pyroelectric energy harvesters for practical applications. Concepts related to macroscopic devices such as regeneration and heat exchange conditions using thermal control elements for thermal energy harvesting are also discussed. This article aims to provide a comprehensive overview of the advancements, challenges, and future directions in the field of non-linear pyroelectric energy harvesting.