posted on 2023-12-14, 17:04authored byJian Wang, Zhaojin Li, Qiujun Wang, Huilan Sun, Haw Jiunn Woo, Shujahadeen B. Aziz, N. Z. Nik Husin, Ramesh T. Subramaniam, Bo Wang
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.