Phase structure analysis and pyroelectric energy harvesting performance of Ba(Hf_xTi_1‐x)O₃ ceramics

Abstract

Ba(Ti1‐xHfx)O3 ceramics were synthesized by a solid‐state reaction process. The evolution of the phase structure was identified by XRD spectrum, dielectric spectroscopy, and temperature‐dependent Raman spectroscopy for the Ba(Ti1‐xHfx)O3 ceramics. In addition, pyroelectric energy harvesting properties based on the Olsen cycle were investigated for the first time. A maximum pyroelectric energy harvesting density value of ND = 491.30 kJ/m3 (ΔT = 120°C, EH = 50 kV/cm) was achieved in the Ba(Hf0.05Ti0.95)O3 ceramic. Compared with those of BT, the values of ND more than doubled in the temperature range from ΔT = 60°C to ΔT = 100°C in the Ba(Hf0.05Ti0.95)O3 ceramic and even increased 3.2 times at ΔT = 80°C near the Curie temperature (TC) of the Ba(Hf0.05Ti0.95)O3 sample. In addition, a larger pyroelectric energy harvesting density value of ND = 367.10 kJ/m3 (ΔT = 120°C, EH = 50 kV/cm) was acquired in the Ba(Hf0.12Ti0.88)O3 ceramic. Values of ND‐BHT5/ND‐BT and ND‐BHT12/ND‐BT were analyzed in the Ba(Ti1‐xHfx)O3 ceramics. The optimal pyroelectric properties can be obtained in the vicinity of the ferroelectric to paraelectric phase‐transition region.

Enhanced electrocaloric effect, energy storage density and pyroelectric response from a domain-engineered lead-free BaTi0.91Sn0.08Zr0.01O3 ferroelectric ceramic

“…The potential energy harvesting based on the Olsen cycle in various BT-based ceramics is presented in Table 4. 31,71,[93][94][95] It can be seen that N D of the prepared BTSZ ceramic is comparable to those of other BT-based bulk ceramics. The normalized energy harvest per unit of temperature change N D DT as well as the normalized energy harvest per unit of electric eld change N D DE were calculated to evaluate the signicance of our ceramic in the eld of energy recovery.…”