Two Birds with One Stone: V 4 C 3 MXene Synergistically Promoted VS 2 Cathode and Zinc Anode for High-Performance Aqueous Zinc-Ion Batteries.

Aqueous zinc-ion batteries (AZIBs) are considered to be a rising star in the large-scale energy storage area because of their low cost and environmental friendliness properties. However, the limited electrochemical performance of the cathode and severe zinc dendrite of the anode severely hinder the practical application of AZIBs. Herein, a novel 3D interconnected VS 2 ⊥V 4 C 3 T x heterostructure material is prepared via one-step solvothermal method. Morphological and structural characterizations show that VS 2 nanosheets are uniformly and dispersedly distributed on the surface of the V 4 C 3 MXene substrate, which can effectively suppress volume change of the VS 2 . Owing to the open heterostructure along with the high conductivity of V 4 C 3 MXene, the VS 2 ⊥V 4 C 3 T x cathode shows a high specific capacity of 273.9 mAh g -1 at 1 A g -1 and an excellent rate capability of 143.2 mAh g -1 at 20 A g -1 . The V 4 C 3 MXene can also effectively suppress zinc dendrite growth when used as protective layer for the Zn anode, making the V 4 C 3 T x @Zn symmetric cell with a stable voltage profile for ≈1700 h. Benefitting from the synergistic modification effect of V 4 C 3 MXene on both the cathode and anode, the VS 2 ⊥V 4 C 3 T x ||V 4 C 3 T x @Zn battery exhibits a long cycling lifespan of 5000 cycles with a capacity of 157.1 mAh g -1 at 5A g -1 .