Engineering multifunctional superstructure cathodes to
conquer
the critical issue of sluggish kinetics and large volume changes associated
with divalent Zn-ion intercalation reactions is highly desirable for
boosting practical Zn-ion battery applications. Herein, it is demonstrated
that a MoS2/C19H42N+ (CTAB)
superstructure can be rationally designed as a stable and high-rate
cathode. Incorporation of soft organic CTAB into a rigid MoS2 host forming the superlattice structure not only effectively initiates
and smooths Zn2+ transport paths by significantly expanding
the MoS2 interlayer spacing (1.0 nm) but also endows structural
stability to accommodate Zn2+ storage with expansion along
the MoS2 in-plane, while synchronous shrinkage along the
superlattice interlayer achieves volume self-regulation of the whole
cathode, as evidenced by in situ synchrotron X-ray
diffraction and substantial ex situ characterizations.
Consequently, the optimized superlattice cathode delivers high-rate
performance, long-term cycling stability (∼92.8% capacity retention
at 10 A g–1 after 2100 cycles), and favorable flexibility
in a pouch cell. Moreover, a decent areal capacity (0.87 mAh cm–2) is achieved even after a 10-fold increase of loading
mass (∼11.5 mg cm–2), which is of great significance
for practical applications. This work highlights the design of multifunctional
superlattice electrodes for high-performance aqueous batteries.