Synthesis and Characterization of Multifunctional High-Entropy Perovskite Oxides

The scientific community has taken a keen interest in perovskite oxides (ABO₃) due to their unique electrical, magnetic, thermal, and optical characteristics with diverse potential applications. The addition of compositional diversity or “high entropy” in these oxide perovskites with five or more cations on a given lattice site offers the opportunity for property engineering by taking advantage of the high compositional disorder, large lattice distortion tunability, huge mass fluctuation, expansion in cation size variance and integration of diverse cation species &lt;!--[endif]----&gt;[1-3]. High entropy perovskites have the potential to revolutionize applications in areas including energy storage, electronics, and photonics, however, designing such compositionally complex multifunctional perovskite oxides is challenging and needs to take into account several factors, including e.g. cation choice for property integration, tolerance factor of the desired structure, high mixing enthalpy, and changing oxidation states. Herein, we present the synthesis of a group of new entropy-stabilized perovskite oxides with a series of alkaline and rare earths on the A site and five transition metals on the B site in equimolar amounts. Such compositions are interesting due to their high cation size variance, and diversity in cation species. Energy dispersive X-ray spectroscopy (EDS) and room temperature X-ray diffraction (XRD) were used to confirm the elemental distribution and single-phase compositions. Electrical, magnetic, and optical properties will be presented for various cation combinations to explore possible multifunctionality. <br/><br/>1. Mazza, A.R., et al., <i>Variance induced decoupling of spin, lattice, and charge ordering in perovskite nickelates.</i> Physical Review Research, 2023. <b>5</b>(1): p. 013008.<br/>2. Mazza, A.R., et al., <i>Designing magnetism in high entropy oxides.</i> Advanced Science, 2022. <b>9</b>(10): p. 2200391.<br/>3. Zheng, Y., et al., <i>Electrical and thermal transport behaviours of high-entropy perovskite thermoelectric oxides.</i> Journal of Advanced Ceramics, 2021. <b>10</b>: p. 377-384.<br/>&lt;!--![endif]----&gt;