Solid State Refrigeration Potential in Lead-free Ferroelectric Ceramic. Investigation of Solid State Refrigeration Potential in Ba0.85Ca0.15Zr0.1Ti0.9O3-based Ferroelectric Ceramics

      Аннотация: This book attempts to shed light on the use of various physical and chemical routes towards the systematic investigation of exploring and enhancing (electro) caloric effects in bulk lead-free Ba0.85Ca0.15Zr0.1Ti0.9O3(BCZT) ceramics composition. Caloric effects were estimated by indirect predictions using Maxwell’s relations in conjunction with experimental data. Electrocaloric(EC) effect in BCZT, Ba0.85Ca0.15Zr0.1Ti0.9-xFexO3 and Ba0.85Sr0.15Ti0.9Zr0.1O3(BSTZ) are found as 0.41K (0-21.5kV/cm), 0.86K (0-37kV/cm) and 2.4K at 303K (0-37kV/cm), respectively. Further, Ba0.85Ca0.075Sr0.075Ti0.9Zr0.1O3(BCSTZ) exhibits temperature invariant performance in spanning 60K (303K-363K). The BCSTZ and BSTZ ceramics have an improved electrocaloric behavior (1.5±0.1K and 2.4K) at an optimum sintering temperature of 1475°C and 1450°C for dwell time of 5hr and 4hr, respectively. A remarkably large elastocaloric response (?Tmax of 1.55K) is observed in BCZT at 340K. Finally, a novel cycle was proposed for suitably combining the multicaloric response using the same material. Additionally, inverse piezocaloric, flexocaloric and barocaloric effect in BCZT, (Ba0.67Sr0.37)TiO3, and PVDF was observed.

Ключевые слова: Lead-free ceramics, electrocaloric, Elastocaloric, Solid-state refrigeration