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DOE OSTI · 2575234

Coupling Anionic Oxygen Redox with Selenium for Stable High‐Voltage Sodium Layered Oxide Cathodes

Xue, Zhichen [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Synchrotron Radiation Lightsource (SSRL)]·Bothra, Neha [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). SUNCAT Center for Interface Science and Catalysis]·Meng, Dechao [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Synchrotron Radiation Lightsource (SSRL)]·Feng, Guangxia [Stanford Univ., CA (United States)]·Li, Yuqi [Stanford Univ., CA (United States)]·Cui, Tony [Stanford Univ., CA (United States)]·Hao, Hongchang [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)]·Lee, Sang‐Jun [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Synchrotron Radiation Lightsource (SSRL)]·Liu, Yijin [Univ. of Texas, Austin, TX (United States)]·Bajdich, Michal [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). SUNCAT Center for Interface Science and Catalysis] (ORCID:0000000311688616)·Nanda, Jagjit [Stanford Univ., CA (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)]·Zheng, Xueli [Stanford Univ., CA (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)]
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Abstract

Utilizing anion redox reaction is crucial for developing the next generation of high-energy density, low-cost sodium-ion batteries. However, the irreversible oxygen redox reaction in Na-ion layered cathodes, which leads to voltage fading and reduced overall lifespan, has hindered their practical application. In this study, selenium is incorporated as a synergistic redox active center of oxygen to improve the stability of Na-ion cathodes. The redesigned cathode maintains stable voltage by demonstrating reversible oxygen redox while significantly suppressing the redox activity of manganese. The anionic redox contribution capacity of the selenium-doped Na 0.6 Li 0.2 Mn 0.8 O 2 cathode remains as high as 84% after 50 cycles, while the pristine Na 0.6 Li 0.2 Mn 0.8 O 2 cathode experiences a reduction to 39% of its initial capacity. The X-ray photoelectron spectroscopy data and computational analysis further revealed that selenium doping participates in redox as Se +4/5 which stabilizes the charged state and increases the energy step for O─O dimerization, thus improving the stability and lifespan of Na 0.6 Li 0.2 Mn 0.8 O 2 cathodes. In conclusion, the findings highlight the potential of redox coupling design to address the issue of voltage fade caused by irreversible anionic redox.

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25 ENERGY STORAGEanion redox chemistrylayered oxide cathodematerials sciencesodium ion battery

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Xue, Zhichen [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Synchrotron Radiation Lightsource (SSRL)], Bothra, Neha [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). SUNCAT Center for Interface Science and Catalysis], Meng, Dechao [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Synchrotron Radiation Lightsource (SSRL)], Feng, Guangxia [Stanford Univ., CA (United States)], Li, Yuqi [Stanford Univ., CA (United States)], Cui, Tony [Stanford Univ., CA (United States)], Hao, Hongchang [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)], Lee, Sang‐Jun [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Synchrotron Radiation Lightsource (SSRL)], Liu, Yijin [Univ. of Texas, Austin, TX (United States)], Bajdich, Michal [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). SUNCAT Center for Interface Science and Catalysis] (ORCID:0000000311688616), Nanda, Jagjit [Stanford Univ., CA (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)], Zheng, Xueli [Stanford Univ., CA (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)]. 2024-12-26. Coupling Anionic Oxygen Redox with Selenium for Stable High‐Voltage Sodium Layered Oxide Cathodes. https://doi.org/10.1002/adfm.202417758

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