One-step Solid-State Synthesis of V_1.13Se₂/V₂O₃ Heterostructure as a High Pseudocapacitance Anode for Fast-Charging...

Sodium-ion batteries (SIBs) offer several benefits, including cost-efficiency and fast-charging characteristics, positioning them as attractive substitutes for lithium-ion batteries in energy storage applications. However, the inferior capacity and cycling stability of electrodes in SIBs necessitate further enhancement due to sluggish reaction kinetics. In this respect, the utilization of heterostructures, which can provide an inherent electric field and abundant active sites on the surface, has emerged as a promising strategy for augmenting the cycling stability and rate features of the electrodes. This work delves into the utilization of V_1.13Se₂/V₂O₃ heterostructure materials as anodes, initially fabricated via a simplified one-step solid-state sintering technique. The high pseudocapacitance and low characteristic relaxation time constant give the V_1.13Se₂/V₂O₃ heterostructure impressive properties, such as a high capacity of 328.5 mAh g^-1 even after 1500 cycles at a high current density of 2 A g^-1 and rate capability of 278.9 mAh g^-1 at 5 A g^-1. Moreover, the assembled sodium-ion full battery delivers a capacity of 118.5 mAh g^-1 after 1000 cycles at 1 A g^-1. These findings provide novel insight and guidance for the rapid synthesis of heterojunction materials and the advancement of SIBs.