Pyroelectric/electrocaloric energy scanvenging and cooling capabilities in ferroelectric materials

摘要: Current needs for clean energy sources aroused the problem of scavenging. Significant advances have been achieved in framework harvesting on solar energy, wind and vibrations (mechanical quantities). Different systems are already available: cells, electromechanical conversion from or mechanical stress (i.e. produced by a person walking an object movement) [1]. Wasted heat is rarely harvested, mainly because very low efficiency devices their large consumption. Pyroelectric materials may be used scavenging, due to ability convert temperature variations into usable electric energy. The reverse effect pyroelectric activity electrocaloric effect. (ECE) general property dielectrics change under applied field at adiabatic conditions. When having exchange with outer medium, it defines exchanged as function isothermal In case ferroelectric ECE strongly correlated effect, which gives induction given variation. refrigeration whereas temperature/heat sensors harvesting. Electrocaloric were focus significant scientific interest 1960s 1970s, but not commercially exploited effects insufficient practical applications [2]. (1-x)Pb(Mg1/3Nb2/3)O3xPbTiO3 (PMN-PT) show quite high [3,4]. However use such limitations before breakdown. It fact limited 3–5 kV/mm bulk ceramics, could largely increased fields up 50–100 kV/mm. Such associated outstanding obtained PZT thin films shown Mischenko et al. [5] predicted controllable 12 K 25 V input voltage.