文摘
Hafnia (HfO<sub>2sub>)-zirconia (ZrO<sub>2sub>) solid solution films show giant positive (ΔT = 13.4 K) and negative (ΔT = −10.8 K) electrocaloric effects that can be simply controlled by tuning the Hf/Zr ratio. It is expected that the combination of the electrocaloric effects with opposite signs in this lead-free, simple, binary oxide can significantly improve the efficiency of electrocaloric cooling.