Energy conversion and storage using artificially induced antiferroelectricity in HfO2/ZrO2 nanolaminates

The field-induced transition, which is useful for converting between electrical and thermal energy, was induced in artificially designed complementary-metal–oxide–semiconductor-compatible HfO2/ZrO2 nanolaminates. The electrocaloric effect in HfO2/ZrO2 nanolaminates was affected by the stacking order, attributed to differences in the relative fraction of the nonferroelectric monoclinic phase, and by the aspect ratio, reflecting crystallographic similarities to the tetragonal or orthorhombic phase. An adiabatic temperature change of up to 12.25 K was achieved using a HfO2/ZrO2 bilayer sample. Furthermore, as an electrostatic supercapacitor, the energy storage density reached 49.90 J/cm3.