A perovskite solid-solution, (1-x)KNbO3-xBaNi1/2Nb1/2O3-? (KBNNO), has been found to exhibit tunable bandgaps in the visible light energy range, making it suitable for light absorption and conversion applications, e.g., solar energy harvesting and light sensing. Such a common ABO3–type perovskite structure, most widely used for ferroelectrics and piezoelectrics, enables the same solid-solution material to be used for the simultaneous harvesting or sensing of solar, kinetic, and thermal energies.
In summary, 0.1KBNNO ceramics with both a standard stoichiometry and with a modified K-to-Nb ratio have been fabricated and characterized in terms of their ferroelectric, pyroelectric, and piezoelectric properties. The samples have been found to exhibit better pyroelectric and piezoelectric coefficients than ZnO and AlN, which could also be used for harvesting and detecting solar, kinetic, and thermal energies/signals. Meanwhile, as the bandgap of 0.1KBNNO is more feasible for visible light energy conversion than that of the parental composition, it may be considered a proper and capable candidate to trigger developments of all-in-one hybrid energy harvesting and multi-functional sensing devices based on only a single piece of material. Further compositional optimization and device fabrication are on-going.
Ferroelectric, pyroelectric, and piezoelectric properties of a photovoltaic perovskite oxide