Yang Zhen-Dong, Chang Zhi-Wen, Zhang Qi, Huang Keke, Zhang Xin-Bo
Key Laboratory of Automobile Materials, Ministry of Education, Department of Materials Science and Engineering, Jilin University, Changchun 130022, China; State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
Sci Bull (Beijing). 2018 Apr 15;63(7):433-440. doi: 10.1016/j.scib.2018.02.014. Epub 2018 Feb 13.
A facile synthesis of the hierarchically porous cathode with MoC nanoparticles through the electrospinning technique and heat treatment is proposed. The carbonization temperature of the precursors is the key factor for the formation of MoC nanoparticles on the carbon nanofibers (MCNFs). Compared with the MoN nanoparticles embedded into N-doped carbon nanofibers film (MNNFs) and N-doped carbon nanofibers film (NFs), the battery with MCNFs cathode is capable of operation with a high-capacity (10,509 mAh g at 100 mA g), a much reduced discharge-charge voltage gap, and a long-term life (124 cycles at 200 mA g with a specific capacity limit of 500 mAh g). These excellent performances are derived from the synergy of the following advantageous factors: (1) the hierarchically self-standing and binder-free structure of MCNFs could ensure the high diffusion flux of Li and O as well as avoid clogging of the discharge product, bulk LiO; (2) the well dispersed MoC nanoparticles not only afford rich active sites, but also facilitate the electronic transfer for catalysis.
提出了一种通过静电纺丝技术和热处理轻松合成具有MoC纳米颗粒的分级多孔阴极的方法。前驱体的碳化温度是在碳纳米纤维（MCNF）上形成MoC纳米颗粒的关键因素。与嵌入N掺杂碳纳米纤维膜（MNNF）和N掺杂碳纳米纤维膜（NF）中的MoN纳米颗粒相比，具有MCNF阴极的电池能够在高容量（100 mA g时为10,509 mAh g）、大大减小的充放电电压差和长寿命（200 mA g时124次循环，比容量限制为500 mAh g）下运行。这些优异的性能源自以下有利因素的协同作用：（1）MCNF的分级自立且无粘结剂结构可确保Li和O的高扩散通量，并避免放电产物LiO堵塞；（2）分散良好的MoC纳米颗粒不仅提供丰富的活性位点，还促进催化的电子转移。
