Basic Principles and Measurement Techniques of Electrocaloric Effect in Ferroelectric Materials

The development of innovative refrigeration technologies becomes essential for the reduction of hazardous gas emissions in conventional cooling systems. In this context, electrocaloric effect (ECE)-based cooling technology seems to be a promising alternative to the conventional vapor compression-based cooling technology due to its unique advantages such as high efficiency, easy miniaturization and integration, eco-friendly, lightweight, and low cost. Therefore, in this chapter, first we discuss the working principle, a brief history, the mechanism, different theoretical approaches, and different direct and indirect measurement techniques for quantifying ECE. Further, we focus on the recent developments and different strategies that are adopted to enhance ECE in different lead-based and lead-free ferroelectrics that include barium titanate-based, sodium potassium niobate-based, and nano-scale binary oxide (ZrO 2 , HfO 2 )-based materials.