Xu Jie, Hong Yuqi, Dou Shuming, Wu Junhan, Zhang Jingchao, Wang Qingmeng, Wen Tiantian, Song Yang, Liu Wei-Di, Zeng Jianrong, Huang Guangsheng, Xu Chaohe, Chen Yanan, Yue Jili, Wang Jingfeng, Pan Fusheng
National Innovation Center for Industry-Education Integration of Energy Storage Technology, College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China.
Chongqing Institute of New Energy Storage Materials and Equipment, Chongqing 401122, China.
Nano Lett. 2025 Jan 15;25(2):730-739. doi: 10.1021/acs.nanolett.4c04908. Epub 2025 Jan 3.
Rechargeable magnesium ion batteries (RMBs) have drawn extensive attention due to their high theoretical volumetric capacity and low safety hazards. However, divalent Mg ions suffer sluggish mobility in cathodes owing to the high charge density and slow insertion/extraction kinetics. Herein, it is shown that an ultrafast nonequilibrium high-temperature shock (HTS) method with a high heating/quenching rate can instantly introduce oxygen vacancies into the olivine-structured MgFeSiO cathode (MgFeSiO-HTS) in seconds. As a proof of concept, the MgFeSiO-HTS exhibits a higher electrochemical property and fast insertion/extraction kinetics in comparison to those prepared from the conventional sintering method. The MgFeSiO-HTS displays remarkable long-term cycling lifespan properties with a reversible capacity of 85.65 and 54.43 mAh g over 500 and 1600 cycles at 2 and 5 C, respectively. Additionally, by combining the electrochemical experiments and density functional theory calculations, oxygen vacancies can weaken the interaction and energy barrier between the Mg ions and the cathode, enhancing the Mg diffusion kinetics.
可充电镁离子电池（RMBs）因其高理论体积容量和低安全风险而备受广泛关注。然而，由于二价镁离子的高电荷密度和缓慢的嵌入/脱出动力学，其在阴极中的迁移速度较慢。在此，研究表明，一种具有高加热/淬火速率的超快非平衡高温冲击（HTS）方法能够在数秒内将氧空位瞬间引入到橄榄石结构的MgFeSiO阴极（MgFeSiO-HTS）中。作为概念验证，与传统烧结方法制备的阴极相比，MgFeSiO-HTS表现出更高的电化学性能和快速的嵌入/脱出动力学。MgFeSiO-HTS分别在2C和5C下经过500次和1600次循环后，展现出显著的长期循环寿命性能，可逆容量分别为85.65和54.43 mAh g。此外，通过结合电化学实验和密度泛函理论计算，氧空位可以削弱镁离子与阴极之间的相互作用和能垒，增强镁的扩散动力学。
