Xia, Shu-Biao, Yao, Li-Feng, Guo, Hong, Shen, Xiang, Liu, Jia-Ming, Cheng, Fei-Xiang, and Liu, Jian-Jun
Tin (Sn)-based materials are potential alternatives to the commercial graphite anode for next-generation Li-ion batteries (LIBs) due to their high theoretical capacity. However, the poor cyclic stability, originating from the large volumetric changes during charge/discharge process, hinder their practical utilization. Herein, we have successfully prepared a Sn-based metal-organic framework (MOF, Sn-PMA), and explored as potential anode materials in LIBs. Benefiting from its layered structure and efficient electron transport channels, Sn-PMA electrodes deliver a high initial capacity of 1567 mAh g−1, at 100 mA g−1, and maintained a reversible capacity of 707 mAh g−1, at 800 mA g−1, after 400 cycles. Furthermore, the detailed post-electrochemical structural, morphological and compositional analysis is carried out to unveil the structural changes and Li-ion storage mechanism of electrodes. Ex-situ XRD and XPS results revealed that, in Sn-PMA electrode, O atom, coordinated to the Sn atom, exhibited higher electronegativity, served as major Li-ion storage site and rendered excellent cyclic stability due to a stable structure. Kinetic analyses reveal that the excellent performance of the Sn-PMA is typical attributed to the pseudocapacitive contribution induced by the special porous structure. A Sn-based MOF has successfully prepared by hydrothermal reaction, which shows outstanding lithium storage properties. Image 1 • Sn-based MOF was fabricated through a simple hydrothermal reaction. • Sn-PMA exhibits excellent electrochemical performance with typical pseudocapacitive contribution. • Ex-situ XRD and XPS reveal the lithium storage mechanism of Sn-PMA. [ABSTRACT FROM AUTHOR]