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 gridscale 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.