Constructing cation-coupled MoSe2/FeSe/C heterostructures for rapid and efficient sodium ion transport

• Main Authors: Wang, Jian, Li, Zhaojin, Wang, Qiujun, Sun, Huilan, Woo, Haw Jiunn, Aziz, Shujahadeen B., Husin, N. Z. Nik, T. Subramaniam, Ramesh, Wang, Bo
• Format: Article
• Published: American Chemical Society 2024
• Subjects: QC Physics
• Online Access: http://eprints.um.edu.my/44984/
• Institution: Universiti Malaya

Low electron conductivity and slow ion dynamics are the two key barriers limiting the use of transition-metal selenide (TMSe) anodes for high-power energy storage device applications. A rational structural design for TMSe can effectively promote the rapid transfer of Na+ on the surface and bulk phase. Presently, a cation-coupled MoSe2/FeSe/C heterostructure is developed by a facile two-step reaction and applied to sodium ion batteries/capacitors (SIBs/SICs). Wherein, a unique edge mixed phase (1T/2H-MoSe2) is generated under Fe induction. Additionally, the metal-organic framework-derived carbon guarantees structural stability and provides support for the rapid adsorption and transport of Na+ on the surface and bulk. Significantly, density functional theory (DFT) calculations verify that the constructed MoSe2/FeSe heterogeneous interface has a strong metallic property that can facilitate the rapid transfer of electrons and ions within the bulk phase. As a result, the prepared MoSe2/FeSe/C can deliver a high specific capacity of 597.2 mA h g-1 (after 1000 cycles) at a current density of 2 A g-1 when applied as the anode of SIBs. Impressively, 3000 cycles can be stabilized, even at a high current density of 10 A g-1. When applied to SIC anodes, a capacity retention of 80.4 can be achieved at 2 A g-1 after 8000 cycles. The strategy of combining cation-coupled induced phase transitions with heterostructure design can serve as a reference for exploring the potential of TMSe in high-power energy storage devices. © 2023 American Chemical Society