Phys.org March 9, 2023
The larger diameter of Na ions compared to Li ions makes the sodiation/desodiation process more difficult with a larger volumetric variation of the electrode material, leading to poor capacity and cycling stability. Researchers in China developed an atomic-interface of well-constructed 2H-MoS2/Fe(SA)-N-C anode assembled with 2H-MoS2 layer and N-doped carbon-confined Fe atom, which boosted the reversible sodium storage capacity. They found that driven by the work function difference at the heterointerface, the electron could transfer from Fe(SA)-N-C to 2H-MoS2 easily, enhancing the adsorption Na+ ion at the S sites of electron-rich MoS2. They indicated that the change in spin-state of the Fe site of Fe(SA)-N-C optimized the electronic structure and catalytic activity of the Fe site. Compared with nitrogen-doped carbon (N-C) and pure carbon, the Fe sites of Fe(SA)-N-C effectively promoted the phase transition and structural evolution of 1T/2H-MoS2 during the sodiation/desodiation process, thus prolonging the lifetime of the material. The 2H-MoS2/Fe(SA)-N-C anode showed a robust long-term cycling performance with a capacity of 350 mA h g-1 after 2,000 cycles at 2.0 A g-1… read more. TECHNICAL ARTICLEÂ
