Han Xiaomin, Wu Feng, Zhao Ran, Bai Ying, Wu Chuan
Beijing Key Laboratory of Environmental Science and Engineering, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing 100081, PR China.
Yangtze Delta Region Academy of Beijing Institute of Technology, Jiaxing 314019, PR China.
ACS Appl Mater Interfaces. 2023 Feb 8;15(5):6888-6901. doi: 10.1021/acsami.2c20473. Epub 2023 Jan 25.
Rechargeable aluminum batteries (RABs) are gaining widespread attention for large-scale energy storage applications as a result of their high energy densities, high security, and abundance. The key to sustain the progress of RABs lies in the quest for the proper cathode materials with prominent capacity and reversible cycle life. Herein, we propose a tremella-like VS as a cathode material aiming to tackle this problem. Obtained from a morphology modification process, VS with a unique nanosheet structure provides sufficient active sites for intercalation and conversion reactions, shortens the transport paths for charge carrier ions, and facilitates the infiltration process for electrolyte. The RAB with the VS cathode exhibits excellent electrochemical performance, including outstanding specific capacity (407.9 mAh g) and stable cycling performance (∼300 cycles at a high current density). The energy storage mechanism has been comprehensively investigated and is confirmed to be a combination of the intercalation/deintercalation of Al and AlCl ions and conversion reaction by various techniques and DFT calculation. Our study not only provides a peculiar and simple strategy for the rational design of metal sulfide cathode materials with high capacity and long-term stability but also proposes a specific energy storage mechanism that guides the development of cathode materials of RABs in the future.
由于具有高能量密度、高安全性和丰富性，可充电铝电池（RABs）在大规模储能应用中受到广泛关注。维持RABs发展的关键在于寻找具有突出容量和可逆循环寿命的合适阴极材料。在此，我们提出一种银耳状的VS作为阴极材料以解决这一问题。通过形貌改性过程获得的具有独特纳米片结构的VS为嵌入和转化反应提供了足够的活性位点，缩短了电荷载流子离子的传输路径，并促进了电解质的渗透过程。具有VS阴极的RAB表现出优异的电化学性能，包括出色的比容量（407.9 mAh g）和稳定的循环性能（在高电流密度下约300次循环）。通过各种技术和密度泛函理论（DFT）计算，对储能机制进行了全面研究，并证实其为Al和AlCl离子的嵌入/脱嵌与转化反应的结合。我们的研究不仅为合理设计具有高容量和长期稳定性的金属硫化物阴极材料提供了一种独特且简单的策略，还提出了一种特定的储能机制，可指导未来RABs阴极材料的发展。
