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DOE OSTI · 2588971

Spinel-Structured High Entropy Oxides: Low Temperature Synthesis, Characterization, and Potential Applications

Algan Simsek, Irem B. [Gazi Univ., Ankara (Türkiye); Drexel Univ., Philadelphia, PA (United States)] (ORCID:0000000152063722)·Badr, Hussein O. [Drexel Univ., Philadelphia, PA (United States)] (ORCID:0000000263553978)·Cardoza, Neal [Drexel Univ., Philadelphia, PA (United States)]·Colin-Ulloa, Erika [Worcester Polytechnic Institute, MA (United States)]·Schwenk, Gregory R. [Drexel Univ., Philadelphia, PA (United States)] (ORCID:0000000310757894)·Sudhakar, Kaustubh [Drexel Univ., Philadelphia, PA (United States)]·Wiedwald, Ulf [University of Duisburg-Essen, Duisburg (Germany)] (ORCID:0000000232094078)·Farle, Michael [University of Duisburg-Essen, Duisburg (Germany)]·Kalra, Vibha [Cornell Univ., Ithaca, NY (United States)] (ORCID:0000000226301560)·Ibrahim, Mohamed A. [Drexel Univ., Philadelphia, PA (United States)]·Titova, Lyubov V. [Worcester Polytechnic Institute, MA (United States)]·Barsoum, Michel W. [Drexel Univ., Philadelphia, PA (United States)] (ORCID:0000000178003517)
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Abstract

High entropy oxides (HEOs) have recently attracted increasing attention due to their remarkable properties and relatively low cost. Herein we report a simple, highly scalable, and low temperature method for synthesizing spinel (FeNiCoCuZn) 3 O 4 (HEO). We heated an aqueous solution containing divalent cations in high alkali environments to temperatures of 25 - 95 °C for 24 h under atmospheric pressure. The HEO, synthesized at 95 °C for 24 h in 1 M KOH, was paramagnetic at room temperature, with a magnetic mass susceptibility of χ = (7.5 ± 0.2) × 10 –7 m 3 ·kg –1 . It demonstrated stable electrochemical lithium storage performance, with a gravimetric capacity of ∼300 mAh·g –1 at 100 mA·g –1 . It was also active in the electrocatalytic oxygen evolution reaction with an overpotential of 460 mV in alkaline media. The band gap energies were in the range of 2.4 eV. Our advancement in the synthesis and processing of transition metal-based HEOs will undoubtedly render them a viable solution for next generation materials for energy production and storage.

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Algan Simsek, Irem B. [Gazi Univ., Ankara (Türkiye); Drexel Univ., Philadelphia, PA (United States)] (ORCID:0000000152063722), Badr, Hussein O. [Drexel Univ., Philadelphia, PA (United States)] (ORCID:0000000263553978), Cardoza, Neal [Drexel Univ., Philadelphia, PA (United States)], Colin-Ulloa, Erika [Worcester Polytechnic Institute, MA (United States)], Schwenk, Gregory R. [Drexel Univ., Philadelphia, PA (United States)] (ORCID:0000000310757894), Sudhakar, Kaustubh [Drexel Univ., Philadelphia, PA (United States)], Wiedwald, Ulf [University of Duisburg-Essen, Duisburg (Germany)] (ORCID:0000000232094078), Farle, Michael [University of Duisburg-Essen, Duisburg (Germany)], Kalra, Vibha [Cornell Univ., Ithaca, NY (United States)] (ORCID:0000000226301560), Ibrahim, Mohamed A. [Drexel Univ., Philadelphia, PA (United States)], Titova, Lyubov V. [Worcester Polytechnic Institute, MA (United States)], Barsoum, Michel W. [Drexel Univ., Philadelphia, PA (United States)] (ORCID:0000000178003517). 2025-08-25. Spinel-Structured High Entropy Oxides: Low Temperature Synthesis, Characterization, and Potential Applications. https://doi.org/10.1021/acsomega.5c00902

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