Developing flexible electrodes for the application in
sodium-ion
batteries (SIBs) has received great attention and has been still challenging
due to their merits of additive-free, lightweight, and high energy
density. In this work, a free-standing 3D flexible SIB anode with
the composition of SnO2@hard carbon@MoS2@soft
carbon is designed and successfully synthesized. This electrode combines
the energy storage advantages and hybrid sodium storage mechanisms
of each material, manifested in the enhanced flexibility, specific
capacity, conductivity, rate, cycling performances, etc. Based on
the synergistic effects, it exhibits much higher specific capacity
than SnO2 carbon nanofibers, as well as more excellent
cycling performance (250 mA h g–1 after 500 cycles
at 1 A g–1) than MoS2 nanospheres (32
mA h g–1). In addition, relevant kinetic mechanisms
are also expounded with the aid of theoretical calculation. This work
provides a feasible and advantageous strategy for constructing high-performance
and flexible energy storage electrodes based on hybrid mechanisms
and synergistic effects.