Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry, Beijing Institute of Technology , Beijing 100081, People's Republic of China.
ACS Appl Mater Interfaces. 2015 Dec 9;7(48):26608-13. doi: 10.1021/acsami.5b08109. Epub 2015 Nov 20.
A novel metal-organic framework (MOF) sandwich coating method (denoted as MOF-SC) is developed for hybrid Li ion battery electrode preparation, in which the MOF films are casted on the surface of a silicon layer and sandwiched between the active silicon and the separator. The obtained electrodes show improved cycling performance. The areal capacity of the cheap and readily available microsized Si treated with MOF-SC can reach 1700 μAh cm(-2) at 265 μA cm(-2) and maintain at 850 μAh cm(-2) after 50 cycles. Beyond the above, the commercial nanosized Si treated by MOF-SC also shows greatly enhanced areal capacity and outstanding cycle stability, 600 μAh cm(-2) for 100 cycles without any apparent fading. By virtue of the novel structure prepared by the MOFs, this new MOF-SC structure serves as an efficient protection cushion for the drastic volume change of silicon during charge/discharge cycles. Furthermore, this MOF layer, with large pore volume and high surface area, can adsorb electrolyte and allow faster diffusion of Li(+) as evidenced by decreased impedance and improved rate performance.
一种新型的金属-有机骨架（MOF）夹层涂层方法（表示为 MOF-SC）被开发用于混合锂离子电池电极的制备，其中 MOF 薄膜被浇铸在硅层的表面上，并夹在活性硅和隔板之间。所得到的电极显示出改善的循环性能。用 MOF-SC 处理的廉价且易于获得的微尺度硅的面容量可以在 265 μA cm(-2)时达到 1700 μAh cm(-2)，并且在 50 个循环后保持在 850 μAh cm(-2)。除此之外，用 MOF-SC 处理的商业纳米硅也表现出极大增强的面容量和出色的循环稳定性，在 100 个循环中没有明显的衰减，容量为 600 μAh cm(-2)。通过 MOFs 制备的新型结构，这种新的 MOF-SC 结构作为在充放电循环期间硅剧烈体积变化的有效保护缓冲层。此外，MOF 层具有大的孔体积和高的表面积，可以吸附电解质并允许 Li(+)更快地扩散，这表现为阻抗降低和改善的倍率性能。
