Key Laboratory of Superlight Materials and Surface Technology (Ministry of Education), College Material Science and Chemical Engineering, Harbin Engineering University, Harbin, 150001, P. R. China.
Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), College of Chemistry, Nankai University, Tianjin, 300071, China.
Small. 2023 Jun;19(26):e2208291. doi: 10.1002/smll.202208291. Epub 2023 Mar 22.
MoS , as a classical 2D material, becomes a capable anode candidate for sodium-ion batteries. However, MoS presents a disparate electrochemical performance in the ether-based and ester-based electrolyte with unclear mechanism. Herein, tiny MoS nanosheets embedded in nitrogen/sulfur-codoped carbon (MoS @NSC) networks are designed and fabricated through an uncomplicated solvothermal method. Thanks to the ether-based electrolyte, the MoS @NSC shows a unique capacity growth in the original stage of cycling. But in the ester-based electrolyte, MoS @NSC shows a usual capacity decay. The increasing capacity puts down to the gradual transformation from MoS to MoS with the structure reconstruction. Based on the above mechanism, MoS @NSC demonstrates an excellent recyclability and the specific capacity keeps around 286 mAh g at 5 A g after 5000 cycles with an ultralow capacity fading rate of only 0.0034% per cycle. In addition, a MoS @NSC‖Na V (PO ) full cell with ether-based electrolyte is assembled and demonstrates a capacity of 71 mAh g , suggesting the potential application of MoS @NSC. Here the electrochemical conversion mechanism of MoS is revealed in the ether-based electrolyte and significance of the electrolyte design on the promoting Na ion storage behavior is highlighted.
二硫化钼（MoS ）作为一种经典的二维材料，成为了钠离子电池有潜力的阳极候选材料。然而，MoS 在基于醚的和基于酯的电解质中表现出截然不同的电化学性能，其具体机制尚不清楚。在此，通过一种简单的溶剂热法设计并制备了嵌入在氮/硫共掺杂碳（MoS @NSC）网络中的微小 MoS 纳米片。得益于基于醚的电解质，MoS @NSC 在循环的初始阶段表现出独特的容量增长。但在基于酯的电解质中，MoS @NSC 表现出通常的容量衰减。容量的增加归因于结构重构过程中 MoS 逐渐向 MoS 的转化。基于上述机制，MoS @NSC 表现出优异的循环稳定性，在 5 A g 的电流密度下经过 5000 次循环后，比容量保持在 286 mAh g 左右，且每个循环的容量衰减率仅为 0.0034%。此外，组装了一个基于醚的电解质的 MoS @NSC‖Na V (PO ) 全电池，其容量为 71 mAh g ，表明了 MoS @NSC 的潜在应用。在此揭示了 MoS 在基于醚的电解质中的电化学转化机制，并强调了电解质设计对促进钠离子存储行为的重要性。
