Wang Wei, Qin Jinwen, Cao Minhua
Department of Chemistry, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Institute of Technology , Beijing 100081, P. R. China.
ACS Appl Mater Interfaces. 2016 Jan 20;8(2):1388-97. doi: 10.1021/acsami.5b10468. Epub 2016 Jan 8.
An interlaced Zn2GeO4 nanofiber network with continuous and interpenetrated mesoporous structure was prepared using a facile electrospinning method followed by a thermal treatment. The mesoporous structure in Zn2GeO4 nanofibers is directly in situ constructed by the decomposition of polyvinylpyrolidone (PVP), while the interlaced nanofiber network is achieved by the mutual fusion of the junctions between nanofibers in higher calcination temperatures. When used as an anode material in lithium ion batteries (LIBs), it exhibits superior lithium storage performance in terms of specific capacity, cycling stability, and rate capability. The pore engineering and the interlaced network structure are believed to be responsible for the excellent lithium storage performance. The pore structure allows for easy diffusion of electrolyte, shortens the pathway of Li(+) transport, and alleviates large volume variation during repeated Li(+) extraction/insertion. Moreover, the interlaced network structure can provide continuous electron/ion pathways and effectively accommodate the strain induced by the volume change during the electrochemical reaction, thus maintaining structural stability and mechanical integrity of electrode materials during lithiation/delithiation process. This strategy in current work offers a new perspective in designing high-performance electrodes for LIBs.
采用简便的静电纺丝法并结合热处理,制备了具有连续且相互贯穿的介孔结构的交错式Zn2GeO4纳米纤维网络。Zn2GeO4纳米纤维中的介孔结构是通过聚乙烯吡咯烷酮(PVP)的分解直接原位构建的,而交错式纳米纤维网络是在较高煅烧温度下通过纳米纤维之间连接点的相互融合实现的。当用作锂离子电池(LIBs)的负极材料时,它在比容量、循环稳定性和倍率性能方面表现出优异的储锂性能。孔工程和交错网络结构被认为是优异储锂性能的原因。孔结构有利于电解质的轻松扩散,缩短Li(+)传输路径,并减轻重复Li(+)萃取/嵌入过程中的大体积变化。此外,交错网络结构可以提供连续的电子/离子通道,并有效适应电化学反应过程中体积变化引起的应变,从而在锂化/脱锂过程中保持电极材料的结构稳定性和机械完整性。当前工作中的这种策略为设计高性能LIBs电极提供了新的视角。