Tuning the kinetics of zinc ion in MoS2 by polyaniline intercalation

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 100 0 cycles. (C) 2021 Elsevier Ltd. All rights reserved.