Liu Dan, Zhang Xinmin, Wang Yan-Jie, Song Shuyan, Cui Lifeng, Fan Hongbo, Qiao Xiaochang, Fang Baizeng
School of Materials Science and Engineering, Dongguan University of Technology, No. 1, Daxue Rd, Songshan Lake, Dongguan, Guangdong, P. R. China.
HEC R&D Center, Institute of Electronic Materials, Dongguan, Guangdong, P. R. China.
Nanoscale. 2020 May 7;12(17):9524-9532. doi: 10.1039/d0nr00866d.
Nanoscaled lanthanide metal-organic frameworks (NLn-MOFs) have emerged as attractive nanomaterials for photofunctional applications. To enhance the inherent properties and endow NLn-MOF materials with desired electrochemical performance for rechargeable Li-O2 batteries, rational design and synthesis of NLn-MOFs with tailored morphologies for high O2 accessibility and rich open metal sites to bind O2 molecules is highly desired and remains a grand challenge. Herein, we prepare Dy-BTC nanospheres, which are explored for the first time as an O2 cathode in Li-O2 batteries. Interestingly, the specific capacity and electrochemical stability of the Dy-BTC nanosphere-based electrode outperform significantly those of the bulk crystalline Dy-BTC. A full discharge capacity of 7618 mA h g-1 at 50 mA g-1 has been achieved by the Dy-BTC nanospheres. Furthermore, the Dy-BTC nanospheres stably deliver a discharge capacity of 1000 mA h g-1 at 200 mA g-1 for 76 cycles, which is remarkably longer than that of the bulk crystalline Dy-BTC with a cycling life of 26 cycles.
纳米级镧系金属有机框架（NLn-MOFs）已成为用于光功能应用的有吸引力的纳米材料。为了增强其固有性能并赋予NLn-MOF材料用于可充电锂氧电池所需的电化学性能，非常需要合理设计和合成具有定制形态的NLn-MOFs，以实现高氧可及性和丰富的开放金属位点来结合氧分子，而这仍然是一个巨大的挑战。在此，我们制备了Dy-BTC纳米球，首次将其作为锂氧电池中的氧阴极进行探索。有趣的是，基于Dy-BTC纳米球的电极的比容量和电化学稳定性明显优于块状晶体Dy-BTC。Dy-BTC纳米球在50 mA g-1下实现了7618 mA h g-1的全放电容量。此外，Dy-BTC纳米球在200 mA g-1下稳定地提供1000 mA h g-1的放电容量达76个循环，这明显长于块状晶体Dy-BTC的26个循环的循环寿命。
