Preparation of promising anode materials with Sn-MOF as precursors for superior lithium and sodium storage

Abstract

Abstract A facile low-temperature aqueous solution method was applied to synthesize Sn-MOF hexahedron, and then the SnO@C, Sn/SnO@C and Sn@C nanocomposites were obtained by H2 reduction using the Sn-MOF as a template at different temperatures. SnO and Sn are embedded in the hexahedral carbon framework with the form of nanorods and nanospheres, respectively. When utilized as anode materials for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs), all the three materials exhibited superior electrochemical performance thanks to the regular hexahedral structure provided by MOFs. Notably, benefiting from the coexistence of rod-like SnO and sphere-like Sn, which is helpful to alleviate the aggregation effect of the sample, Sn/SnO@C exhibited the best rate performance (516.1 mA h g−1 for LIB and 130.1 mA h g−1 for SIB at the current density of 2000 mA g−1) and remarkable cyclability (835.9 mA h g−1 for LIB at 1000 mA g−1 after 200 cycles and 401.5 mA g−1 for SIB at 100 mA g−1 after 100 cycles). The results show that the Sn/SnO@C composite has potential as a practical anode for lithium ion batteries and sodium ion batteries.