Sui Simi, Xie Haonan, Chen Biao, Wang Tianshuai, Qi Zijia, Wang Jingyi, Sha Junwei, Liu Enzuo, Zhu Shan, Lei Kaixiang, Zheng Shijian, Zhou Guangmin, He Chunnian, Hu Wenbin, He Fang, Zhao Naiqin
School of Materials Science and Engineering, Tianjin Key Laboratory of Composite and Functional Materials, Tianjin University, Tianjin, 300350, P. R. China E-mails.
Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology, School of Materials Science and Engineering, Hebei University of Technology, Tianjin, 300401, People's Republic of China.
Angew Chem Int Ed Engl. 2024 Oct 21;63(43):e202411255. doi: 10.1002/anie.202411255. Epub 2024 Sep 2.
Conversion-type electrode materials have gained massive research attention in sodium-ion batteries (SIBs), but their limited reversibility hampers practical use. Herein, we report a bifunctional nanoreactor to boost highly reversible sodium-ion storage, wherein a record-high reversible degree of 85.65 % is achieved for MoS anodes. Composed of nitrogen-doped carbon-supported single atom Mn (NC-SAMn), this bifunctional nanoreactor concurrently confines active materials spatially and catalyzes reaction kinetics. In situ/ex situ characterizations including spectroscopy, microscopy, and electrochemistry, combined with theoretical simulations containing density functional theory and molecular dynamics, confirm that the NC-SAMn nanoreactors facilitate the electron/ion transfer, promote the distribution and interconnection of discharging products (NaS/Mo), and reduce the NaS decomposition barrier. As a result, the nanoreactor-promoted MoS anodes exhibit ultra-stable cycling with a capacity retention of 99.86 % after 200 cycles in the full cell. This work demonstrates the superiority of bifunctional nanoreactors with two-dimensional confined and catalytic effects, providing a feasible approach to improve the reversibility for a wide range of conversion-type electrode materials, thereby enhancing the application potential for long-cycled SIBs.
转换型电极材料在钠离子电池（SIBs）中受到了广泛的研究关注，但其有限的可逆性阻碍了实际应用。在此，我们报道了一种双功能纳米反应器，以促进高度可逆的钠离子存储，其中MoS阳极实现了创纪录的85.65%的高可逆度。这种双功能纳米反应器由氮掺杂碳负载的单原子锰（NC-SAMn）组成，它同时在空间上限制活性材料并催化反应动力学。包括光谱学、显微镜学和电化学在内的原位/非原位表征，结合包含密度泛函理论和分子动力学的理论模拟，证实了NC-SAMn纳米反应器促进了电子/离子转移，促进了放电产物（NaS/Mo）的分布和互连，并降低了NaS分解势垒。结果，纳米反应器促进的MoS阳极表现出超稳定的循环性能，在全电池中经过200次循环后容量保持率为99.86%。这项工作证明了具有二维限制和催化作用的双功能纳米反应器的优越性，为提高广泛的转换型电极材料的可逆性提供了一种可行的方法，从而增强了长循环SIBs的应用潜力。
