Sun Dianding, Liu Kunhong, Hu Junping, Zhou Jisheng
State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Electrochemical Process and Technology for Materials, Beijing University of Chemical Technology, Beijing, 100029, P. R. China.
Petrochemical Research Institute, PetroChina Company Limited, Beijing, 100195, P. R. China.
Small. 2021 Jan;17(4):e2006374. doi: 10.1002/smll.202006374. Epub 2020 Dec 30.
Heterostructures are attracting increasing attention in the field of sodium-ion batteries. However, it is still unclear whether any two monophase components can be used to construct a high-performance heterostructure for sodium-ion batteries, as well as the kind of heterostructures that can boost electrochemical performances. In this study, based on classical semiconductor theories on antiblocking and blocking interfaces, attempts are made to answer the abovementioned queries. For this purpose, NiTe -ZnTe antiblocking and CoTe -ZnTe blocking heterostructures are synthesized through a bimetal-hexamine framework-derived strategy. The NiTe -ZnTe antiblocking heterostructure exhibits excellent high-rate and cycling performances, while the CoTe -ZnTe blocking heterostructure performs poorly, even compared to their monophase components. Further, kinetic measurements and theoretical calculation confirm that antiblocking heterointerfaces can boost Na-ion diffusion efficiency and decrease the diffusion barrier, which can be attributed to the highly conductive antiblocking heterointerfaces generated due to electron transfer from NiTe to ZnTe. Therefore, this study provides a new perspective to design heterostructures more efficiently, with significantly better Na-ion storage performance.
异质结构在钠离子电池领域正吸引着越来越多的关注。然而,目前仍不清楚是否任意两个单相组分都可用于构建高性能的钠离子电池异质结构,以及何种异质结构能够提升电化学性能。在本研究中,基于经典的半导体反阻挡和阻挡界面理论,尝试回答上述问题。为此,通过双金属六胺框架衍生策略合成了NiTe -ZnTe反阻挡和CoTe -ZnTe阻挡异质结构。NiTe -ZnTe反阻挡异质结构展现出优异的高倍率和循环性能,而CoTe -ZnTe阻挡异质结构即使与其单相组分相比性能也较差。此外,动力学测量和理论计算证实,反阻挡异质界面可提高钠离子扩散效率并降低扩散势垒,这可归因于由于电子从NiTe转移至ZnTe而产生的高导电反阻挡异质界面。因此,本研究为更高效地设计具有显著更好钠离子存储性能的异质结构提供了新的视角。