Zhang Juan, Yin Ya-Xia, Guo Yu-Guo
CAS Key Laboratory of Molecular Nanostructure and Nanotechnology, and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences (CAS) , Beijing 100190, PR China.
University of Chinese Academy of Sciences , Beijing 100049, PR China.
ACS Appl Mater Interfaces. 2015 Dec 23;7(50):27838-44. doi: 10.1021/acsami.5b09181. Epub 2015 Dec 8.
Sodium-ion batteries (SIBs) have attracted considerable attention as an alternative energy-storage technology in recent years. Developing advanced sodium storage anode materials with appropriate working potential, high capacity, and good cycling performance is very important. Herein, we demonstrate a nanostructured tellurium@carbon (nano-Te@C) composite by confining nano-Te molecules in the space of carbon micropores as an attractive anode material for SIBs. The nano-Te@C anode presents an appropriate redox potential in the range of 1.05-1.35 V (vs Na(+)/Na), which avoids the Na dendrite problem and achieves a high reversible capacity of 410 mA h g(-1) on the basis of a two-electron redox reaction mechanism. Notably, the nano-Te@C exhibits an admirable long-term cycling stability with a high capacity retention of 90% for 1000 cycles (i.e., ultralow capacity decay of 0.01% per cycle). The excellent electrochemical property of nano-Te@C benefits from the high electroactivity from the nanostructure design and the effective confinement of the microporous carbon host. In addition, a Na-ion full cell by using nano-Te@C as anode and Na2/3Ni1/3Mn2/3O2 as cathode is demonstrated for the first time and exhibits a remarkable capacity retention up to 95% after 150 cycles. The results put new insights for the development of advanced SIBs with long-cycle lifespan.
近年来，钠离子电池（SIBs）作为一种替代储能技术引起了广泛关注。开发具有合适工作电位、高容量和良好循环性能的先进钠存储负极材料非常重要。在此，我们通过将纳米碲分子限制在碳微孔空间中，展示了一种纳米结构的碲@碳（nano-Te@C）复合材料，作为SIBs的一种有吸引力的负极材料。nano-Te@C负极在1.05 - 1.35 V（vs Na(+)/Na）范围内呈现出合适的氧化还原电位，避免了钠枝晶问题，并基于双电子氧化还原反应机制实现了410 mA h g(-1)的高可逆容量。值得注意的是，nano-Te@C表现出令人钦佩的长期循环稳定性，在1000次循环中具有90%的高容量保持率（即每循环超低容量衰减0.01%）。nano-Te@C优异的电化学性能得益于纳米结构设计带来的高电活性以及微孔碳主体的有效限制。此外，首次展示了以nano-Te@C为负极、Na2/3Ni1/3Mn2/3O2为正极的钠离子全电池，在150次循环后表现出高达95%的显著容量保持率。这些结果为开发具有长循环寿命的先进SIBs提供了新的见解。
