Hollow Structure VS₂@Reduced Graphene Oxide (RGO) Architecture for Enhanced Sodium‐Ion Battery Performance

Abstract

As a typical two‐dimensional (2D) layered material, (vanadium disulfide) VS2 has huge potentials for application in SIBs due to its large interlayer spacing and high conductivity compared to metal oxide or other 2D materials. Reduced graphene oxide (RGO) possesses exceptional electronic properties and large specific area favoring fast electron transport and rich redox sites. In this work, VS2 hollow flower spheres and RGO nanocomposites were developed for the first time, it was synthesized using a facile solvothermal method. Benefiting from the exceptional layered structure, when used as the anode material for SIBs at room temperature, the as‐prepared electrode material of VS2 hollow flower spheres @RGO (named as VS2 HFS/RGO) nanocomposites delivers a high reversible discharge specific capacity of around 430 mAh/g at current density of 100 mA/g, superior rate performance (2 A/g) and excellent cycling properties with the discharge capacity remained 350 mAh/g at 100 mA/g after 500 cycles. Results show that the kinetics of VS2 HFS/RGO nanocomposites were mainly a capacitive‐controlled storage process and the high capacity contribution were beneficial for good rate performance. This work could provide new approaches and potentials for exploring and searching high performances anode materials for the practical applications of SIBs.

A Review on the Current Progress and Challenges of 2D Layered Transition Metal Dichalcogenides as Li/Na‐ion Battery Anodes

“…Experimentally it was found that the as‐prepared VS 2 maintained almost 100 % capacity retention even after 600 cycles where the applied current was 5 A g −1 . The composition of VS 2 with carbonaceous materials was also explored to enhance cyclic stability and rate capability [111i,j] . In one of such reports, Xu et al .…”

CuFeS2 as a Very Stable High-Capacity Anode Material for Sodium-Ion Batteries: A Multimethod Approach for Elucidation of the Complex Reaction Mechanisms during Discharge and Charge Processes

“…Many binary transition metal sulfides have already been investigated for application in SIBs such as TiS 2, , MnS, , VS 2 , , or MoS 2 , , and in most cases nanoscaled or specially modified materials like reduced graphene oxide (RGO)-composite materials were used to reach a satisfying rate and cycle stability. Ternary sulfides, on the other hand, have been studied less intensively as electrode materials in SIBs, although the use of such compounds could be beneficial.…”

Insights into the Dynamic Catalytic Effect of Metal Sulfides with Prominent Lithiation Process in the Application of Li–S Batteries

“…However, most of the popular catalysts possess remarkable redox characteristics in a working Li–S system (Scheme ), and the valance state changes of the catalysts during the lithiation/delithiation process are rarely mentioned in most of Li–S catalytic works. − Even if the amount of the adopted catalyst is very limited, the lithiation process will lead to chemical state changes of the catalysts and will surely impose substantial changes to the interaction toward the LiPS. For example, vanadium sulfide (VS 4 ) is a well-known catalyst in Li–S batteries, which has shown superior catalytic activity toward LiPS conversion. − In the operating voltage window of Li–S batteries (1.7–2.8 V), VS 4 tends to transform into Li x VS 4 ( x = 1–3) through a solid-state lithiation process, the valence state of V and S elements will simultaneously change from V 4+ to V 5+ and from S 2 2– to S 2– . − The lithiation process of VS 4 and the valance state change of S and V will all impose remarkable influence in the catalytic mechanism in the Li–S system, whereas this phenomenon is rarely mentioned in related works. ,, Such a phenomenon is also detected in the Mo 6 S 8 -catalyzed Li–S system in which a prominent interaction change toward LiPS is detected due to the lithiated state of LiMo 6 S 8 …”