MOF-Derived Fe₂CoSe₄@NC and Fe₂NiSe₄@NC Composite Anode Materials towards High-Performance Na-Ion Storage

• Published in: Inorganics
• Main Authors: Hangxuan Xie, Wei Zhang, Chao Wang, Shangcheng Zhao, Zhentao Hao, Xiaolian Huang, Kanghua Miao, Xiongwu Kang
• Format: Article
• Language: English
• Published: MDPI AG 2024-06-01
• Subjects: bi-metal selenide; MOF; selenization; robust structure; diffusion
• Online Access: https://www.mdpi.com/2304-6740/12/6/165
• ISSN: 2304-6740

Binary transition metal selenides (BTMSs) are more promising than single transition metal selenides (TMS) as anode materials of sodium-ion batteries (SIBs). However, it is still very challenging to prepare high-performance BTMSs in the pure phase, instead of a mixture of two TMSs. In this study, a binary metal center-based MOF derived selenization strategy was developed to prepare iron–cobalt selenide (Fe₂CoSe₄@NC) and iron–nickel selenide (Fe₂NiSe₄@NC) nanocomposites in the single phase and when wrapped with carbon layers. As the anode material of SIBs, Fe₂CoSe₄@NC exhibits higher long-term cycling performance than Fe₂NiSe₄@NC, maintaining a capacity of 352 mAh g⁻¹ after 2100 cycles at 1.0 A g⁻¹, which is ascribed to the higher percentage of the nanopores, larger lattice spacing, and faster Na+ diffusion rate in the electrode materials of the former rather than the latter.