Synthesis and Electrochemical Performance of SnO Quantum Dots@ UiO-66 Hybrid for Lithium Ion Battery Applications.

A novel method that combines the dehydration of inorganic clusters in metal-organic frameworks (MOFs) with nonaqueous sol-gel chemistry and pyrolysis processes is developed to synthesize SnO quantum dots@Zr-MOFs (UIO-66) composites. The size of as-prepared SnO nanoparticles is approximately 4 nm. Moreover, SnO nanoparticles are uniformly anchored on the surface of the Zr-MOFs, which serves as a matrix to alleviate the agglomeration of SnO grains. This structure provides an accessible surrounding space to accommodate the volume change of SnO during the charge/discharge process. Cyclic voltammetry and galvanostatic charge/discharge were employed to examine the electrochemical properties of the ultrafine SnO@Zr-MOF (UIO-66) material. Benefiting from the advantages of the smaller size of SnO nanoparticles and the synergistic effect between SnO nanoparticles and the Zr-MOFs, the SnO@Zr-MOF composite exhibits enhanced electrochemical performance when compared to that of its SnO bulk counterpart. Specifically, the discharge-specific capacity of the SnO@Zr-MOF electrode can still remain at 994 mA h g at 50 mA g after 100 cycles. The columbic efficiencies can reach 99%.