Negative thermal expansion and oxygen-redox electrochemistry

• 成果类型: Article
• 署名作者: Qiu, Bao; Zhou, Yuhuan; Liang, Haoyan; Zhang, Minghao; Gu, Kexin; Zeng, Tao; Zhou, Zhou; Wen, Wen; Miao, Ping; He, Lunhua; Xiao, Yinguo; Burke, Sven; Liu, Zhaoping; Meng, Ying Shirley
• 署名单位: Chinese Academy of Sciences; Ningbo Institute of Materials Technology & Engineering, CAS; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS; University of Chicago; Peking University; Peking University Shenzhen Graduate School (PKU Shenzhen); Chinese Academy of Sciences; Chinese Academy of Sciences; Institute of High Energy Physics, CAS; Chinese Academy of Sciences; Institute of High Energy Physics, CAS; Chinese Academy of Sciences; Institute of Physics, CAS; University of California System; University of California San Diego
• 刊物名称: Nature
• ISSN/ISSBN: 0028-1612
• DOI: 10.1038/s41586-025-08765-x
• 发表日期: 2025-04-24
• 关键词: anionic redox; cathode materials; capacity; DYNAMICS; faults; oxides; ORDER

摘要

Structural disorder within materials gives rise to fascinating phenomena, attributed to the intricate interplay of their thermodynamic and electrochemical properties1,2. Oxygen-redox (OR) electrochemistry offers a breakthrough in capacity limits, while inducing structural disorder with reduced electrochemical reversibility3, 4-5. The conventional explanation for the thermal expansion of solids relies on the Gr & uuml;neisen relationship, linking the expansion coefficient to the anharmonicity of the crystal lattice6. However, this paradigm may not be applicable to OR materials due to the unexplored dynamic disorder-order transition in such systems7,8. Here we reveal the presence of negative thermal expansion with a large coefficient value of -14.4(2) x 10-6 degrees C-1 in OR active materials, attributing this to thermally driven disorder-order transitions. The modulation of OR behaviour not only enables precise control over the thermal expansion coefficient of materials, but also establishes a pragmatic framework for the design of functional materials with zero thermal expansion. Furthermore, we demonstrate that the reinstatement of structural disorder within the material can also be accomplished through the electrochemical driving force. By adjusting the cut-off voltages, evaluation of the discharge voltage change indicates a potential for nearly 100% structure recovery. This finding offers a pathway for restoring OR active materials to their pristine state through operando electrochemical processes, presenting a new mitigation strategy to address the persistent challenge of voltage decay.