College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science , Shanghai 201620, China.
ACS Appl Mater Interfaces. 2017 Oct 11;9(40):35030-35039. doi: 10.1021/acsami.7b11620. Epub 2017 Sep 26.
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%.
一种新颖的方法，结合了金属有机骨架（MOFs）中无机团簇的脱水作用、非水溶胶-凝胶化学和热解过程，用于合成 SnO 量子点@Zr-MOFs（UIO-66）复合材料。所制备的 SnO 纳米颗粒的尺寸约为 4nm。此外，SnO 纳米颗粒均匀地锚定在 Zr-MOFs 的表面上，后者作为基质可缓解 SnO 晶粒的团聚。这种结构提供了一个可及的周围空间，以适应 SnO 在充放电过程中的体积变化。循环伏安法和恒电流充放电法用于研究超细 SnO@Zr-MOF（UIO-66）材料的电化学性能。得益于 SnO 纳米颗粒的较小尺寸和 SnO 纳米颗粒与 Zr-MOFs 之间的协同效应，SnO@Zr-MOF 复合材料的电化学性能得到了增强，与 SnO 块状相比，其放电比容量在 50mA/g 时仍能保持在 994mAh/g 以上，经过 100 次循环后，其库仑效率可达 99%。
