Wang Wenhao, Zhang Wenwei, Yu Ruohan, Qiao Fan, Wang Jilin, Wang Junjun, An Qinyou
Guangxi Key Laboratory of Optical and Electronic Materials and Devices, Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of Resources, School of Materials Science and Engineering, Guilin University of Technology, Guilin 541004, China.
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China.
ACS Nano. 2024 Dec 16. doi: 10.1021/acsnano.4c11147.
The moderate working voltage and high capacity of transition metal dichalcogenides (TMDs) make them promising anode materials for aqueous calcium-ion batteries (ACIBs). However, the large radius and two charges of Ca cause TMDs to exhibit poor performance in ACIBs. Therefore, effective regulation strategies are crucial for enabling the application of TMDs in ACIBs. Herein, MoS with expanded interlayer spacing and an enriched 1T phase (ES-1T-MoS) is constructed by molecular engineering and reported as an anode material for ACIBs. Molecular engineering increases the capacity of MoS from 29.4 to 91.2 mAh g and improves its rate performance from 20 to 76.1 mAh g at 2.0 A g. ES-1T-MoS also shows a -20 to 50 °C wide temperature working capability. Furthermore, the capacity improvement reasons and the calcium storage mechanism of ES-1T-MoS are revealed through density functional theory calculations and / characterizations. Finally, a "rocking-chair" aqueous calcium-ion pouch cell with a Prussian blue analogue cathode and ES-1T-MoS anode is assembled. The pouch cell exhibits a life of 150 cycles with over 90.8% capacity retention at 0 and 25 °C. This work demonstrates that molecular engineering is an effective strategy to improve the calcium storage performance of TMDs and promotes the advancement of ACIBs.
过渡金属二硫属化物（TMDs）适中的工作电压和高容量使其成为水系钙离子电池（ACIBs）颇具前景的负极材料。然而，Ca的大半径和二价电荷导致TMDs在ACIBs中表现出较差的性能。因此，有效的调控策略对于使TMDs在ACIBs中得到应用至关重要。在此，通过分子工程构建了具有扩大层间距和富集1T相的MoS（ES-1T-MoS），并将其作为ACIBs的负极材料进行报道。分子工程使MoS的容量从29.4 mAh g提高到91.2 mAh g，并将其在2.0 A g电流密度下的倍率性能从20 mAh g提高到76.1 mAh g。ES-1T-MoS还展现出-20至50°C的宽温度工作能力。此外，通过密度泛函理论计算和表征揭示了ES-1T-MoS容量提升的原因及储钙机制。最后，组装了具有普鲁士蓝类似物正极和ES-1T-MoS负极的“摇椅式”水系钙离子软包电池。该软包电池在0和25°C下循环150次后容量保持率超过90.8%。这项工作表明分子工程是提高TMDs储钙性能的有效策略，并推动了ACIBs的发展。
