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While aqueous rechargeable zinc ion batteries (ARZIBs) are one of the promising energy storage devices, it is still a challenge to develop satisfactory cathode materials. Here, a hierarchical hybrid where MoS2 nanosheets with 86% of 1T phase are grown in-situ on reduced graphene oxide scaffolds is proposed to be a superior cathode of ARZIBs. The microstructure of as-prepared hybrid is correlated with its zinc storage performance by electrochemical and spectroscopic characterizations coupled with electron microscopy analysis. They reveal the incorporation of reduced graphene oxide scaffolds effectively stabilizes the 1T phase, exempting, to the maximum, the phase transition associated with the zinc insertion/extraction, reduces the electron transfer resistance and keeps the hierarchical morphology of the nanoscale MoS2 that shortens the zinc ion diffusion path length. All these together develop the pseudocapacitive property of MoS2. As a result, this hybrid electrode delivers a high discharge capacity of 108.3 mAh g−1 at 5.0 A g−1 and retains 88% initial capacity after 1000 cycles. Our strategy sheds some lights on the rational design of MoS2 nanoscale architecture towards superior cathode material of divalent/multivalent aqueous batteries.

Aqueous rechargeable zinc ion batteries (ARZIBs) are one of the promising electrochemical energy storage devices to overcome the worldwide energy challenge. However, the development of a suitable cathode with high energy/power densities and long cycle-life for ARZIBs is still a challenge. Here, a molybdenum disulfide/polyaniline (MoS2/PANI) hybrid with an inter-overlapped heterostructure is firstly explored as a superior cathode of ARZIBs. Its zinc intercalation chemistry is studied by combining means of ex-situ X-ray diffraction, ex-situ Raman, electrochemical analysis and density functional theory calculations. The results suggest an appropriate amount of PANI intercalation into MoS2 interlayer boosts the Zn2+ transport by expanding the interlayer spacing of MoS2 host and partially shielding the electrostatic interactions between Zn2+ and MoS2 host. Also, it enhances the charge transfer efficiency via reducing the bandgap between the conduction bands and valence bands of MoS2. As a result, the MoS2/PANI hybrid delivers a high reversible capacity of 106.5 mAh g − 1 at a current density of 1.0 A g−1 and retains 86% capacity after 1000 cycles.