Boosted zn-ion storage in high crystalline VS4 anode by enhanced diffusion-controlled kinetics

Rechargeable aqueous zinc ion energy storage devices based on Zn metal anode are highly promising for grid-scale energy storage due to their abundant reserves, low cost and remarkable safety; however, they also suffer from the uncontrollable Zn dendrites issue, self-corrosion, surface passivation and poor Zn metal utilization (<5%). In this work, a VS4 anode was regulated by graphene oxide (GO) with an increased crystallinity to form a three-dimensional VS4/reduced GO (3D-VG) anode for advanced zinc-ion batteries and zinc-ion hybrid supercapacitors (ZIBs and ZHCs). The optimized VS4 phase in 3D-VG facilitated a rapid diffusion-controlled dominated electrochemical kinetics. Meanwhile, benefiting from a conductive 3D hierarchical graphene framework anchoring well-distributed VS4 nanoflakes, the 3D-VG hybrid delivered a high reversible capacity of 468 mAh/g after 100 cycles at 1 A/g and kept a stable capacity of 177 mAh/g after 2000 cycles at 5A/g based on a synergetic energy storage mechanism with intercalation and conversion. Based on 3D-VG anode, both of the assembled ZIB and ZHC devices exhibited excellent stability and ultralong lifespans which demonstrated that 3D-VG is a promising anode for zinc ion energy storage devices.