Tuning the Spin Transition and Carrier Type in Rare-Earth Cobaltates via Compositional Complexity

Bibliographische Detailangaben
Veröffentlicht in:	Advanced materials (Deerfield Beach, Fla.). - 1998. - (2024) vom: 23. Aug., Seite e2406885
1. Verfasser:	Zhang, Alan (VerfasserIn)
Weitere Verfasser:	Oh, Sangheon, Choi, Byoung Ki, Rotenberg, Eli, Brown, Timothy D, Spataru, Catalin D, Kinigstein, Eli, Guo, Jinghua, Sugar, Joshua D, Salagre, Elena, Mascaraque, Arantzazu, Michel, Enrique G, Shad, Alison C, Zhu, Jacklyn, Witman, Matthew D, Kumar, Suhas, Talin, A Alec, Fuller, Elliot J
Format:	Online-Aufsatz
Sprache:	English
Veröffentlicht:	2024
Zugriff auf das übergeordnete Werk:	Advanced materials (Deerfield Beach, Fla.)
Schlagworte:	Journal Article cobaltate high entropy oxide spin transition

Beschreibung
Zusammenfassung:	© 2024 Wiley‐VCH GmbH. There is growing interest in material candidates with properties that can be engineered beyond traditional design limits. Compositionally complex oxides (CCO), often called high entropy oxides, are excellent candidates, wherein a lattice site shares more than four cations, forming single-phase solid solutions with unique properties. However, the nature of compositional complexity in dictating properties remains unclear, with characteristics that are difficult to calculate from first principles. Here, compositional complexity is demonstrated as a tunable parameter in a spin-transition oxide semiconductor La1- x(Nd, Sm, Gd, Y)x/4CoO3, by varying the population x of rare earth cations over 0.00≤ x≤ 0.80. Across the series, increasing complexity is revealed to systematically improve crystallinity, increase the amount of electron versus hole carriers, and tune the spin transition temperature and on-off ratio. At high a population (x = 0.8), Seebeck measurements indicate a crossover from hole-majority to electron-majority conduction without the introduction of conventional electron donors, and tunable complexity is proposed as new method to dope semiconductors. First principles calculations combined with angle resolved photoemission reveal an unconventional doping mechanism of lattice distortions leading to asymmetric hole localization over electrons. Thus, tunable complexity is demonstrated as a facile knob to improve crystallinity, tune electronic transitions, and to dope semiconductors beyond traditional means
Beschreibung:	Date Revised 24.08.2024 published: Print-Electronic Citation Status Publisher
ISSN:	1521-4095
DOI:	10.1002/adma.202406885