Yang Mengke, Guo Donglei, Zhang Ting, Liu Guilong, Wu Naiteng, Qin Aimiao, Liu Xianming, Mi Hongyu
School of Chemical Engineering and Technology, Xinjiang University, Urumqi 830046, China.
Key Laboratory of Function-Oriented Porous Materials, College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471934, China.
ACS Omega. 2021 Oct 30;6(44):29609-29617. doi: 10.1021/acsomega.1c03888. eCollection 2021 Nov 9.
Rational construction of anode material architecture to afford excellent cycling stability, fast rate capacity, and large specific capacity is essential to promote further development of lithium-ion batteries in commercial applications. In this work, we propose a facile strategy to anchor ultrafine β-MoC nanoparticles in N-doped porous carbon skeleton (β-MoC@NC) using a scalable salt-template method. The well-defined and abundant hierarchical porous structure of β-MoC@NC can not only significantly enhance the electron/ion transfer but also markedly increase the specific surface area to effectively expose the electrochemically accessible active sites. Besides, the N-doped carbon matrix can turn the d-orbital electrons of the Mo to boost the electron transportation as well as distribute active sites to buffer the volume change of MoC and provide conductive pathways during discharge/charge cycles. As a result, the as-prepared β-MoC@NC displays excellent lithium storage performance in terms of 1701.6 mA h g at 0.1 A g after 100 cycles and a large capacity of 816.47 mA h g at 2.0 A g after 500 cycles. The above results distinctly demonstrate that the β-MoC@NC composite has potential application as anode materials in high-performance energy storage devices.
构建合理的负极材料结构以实现出色的循环稳定性、快速倍率性能和高比容量,对于推动锂离子电池在商业应用中的进一步发展至关重要。在这项工作中,我们提出了一种简便的策略,通过可扩展的盐模板法将超细β-MoC纳米颗粒锚定在氮掺杂多孔碳骨架(β-MoC@NC)中。β-MoC@NC明确且丰富的分级多孔结构不仅可以显著增强电子/离子传输,还能显著增加比表面积,从而有效暴露电化学可及的活性位点。此外,氮掺杂碳基体可以改变Mo的d轨道电子,促进电子传输,并分布活性位点以缓冲MoC的体积变化,同时在充放电循环过程中提供导电路径。结果,所制备的β-MoC@NC在100次循环后,在0.1 A g下表现出1701.6 mA h g的优异锂存储性能,在500次循环后,在2.0 A g下具有816.47 mA h g的大容量。上述结果清楚地表明,β-MoC@NC复合材料作为高性能储能器件的负极材料具有潜在应用价值。