Construction of Hierarchical Nanotubes Assembled from Ultrathin V₃S₄@C Nanosheets towards Alkali‐Ion Batteries with Ion‐Dependent Electrochemical Mechanisms

Abstract

Ultrathin core–shell V3S4@C nanosheets assembled into hierarchical nanotubes (V3S4@C NS‐HNTs) are synthesized by a self‐template strategy and evaluated as general anodes for alkali‐ion batteries. Structural/physicochemical characterizations and DFT calculations bring insights into the intrinsic relationship between crystal structures and electrochemical mechanisms of the V3S4@C NS‐HNTs electrode. The V3S4@C NS‐HNTs are endowed with strong structural rigidness owing to the layered VS2 subunits and interlayer occupied V atoms, and efficient alkali‐ion adsorption/diffusion thanks to the electroactive V3S4‐C interfaces. The resulting V3S4@C NS‐HNTs anode exhibit distinct alkali‐ion‐dependent charge storage mechanisms and exceptional long‐durability cyclic performance in storage of K+, benefiting from synergistic contributions of pseudocapacitive and reversible intercalation/de‐intercalation behaviors superior to those of the conversion‐reaction‐based Li+‐/Na+‐storage counterparts.

Sandwich Structures Constructed by ZnSe⊂N‐C@MoSe2 Located in Graphene for Efficient Sodium Storage

“…[1] LIBs have been regarded as the most likely energy storage device to replace fossil fuels in terms of the maturity of the present LIB technology, high energy density, long lifespan, and environmentally friendliness. [2][3][4] More remarkably, even though LIBs are widely used in electric vehicles, electronic devices, electric grids, and so on, it still faces an enormous challenge of lithium resource depletion (0.065% reserves in the earth's crust). [5][6][7] Fortunately, the working mechanisms and preparation technology of sodium−ion batteries (SIBs) are similar to LIBs.…”

A Universal Strategy toward Ultrasmall Hollow Nanostructures with Remarkable Electrochemical Performance

“…To understand the superior electrochemical performance of ultrasmall hollow nanostructures, we have performed CV at different scan rates (0.1–2 mV s −1 ) to analyze the reaction kinetics for the S‐H‐Fe 2 O 3 /RGO (Supporting Information, Figure S17), L‐H‐Fe 2 O 3 /RGO (Supporting Information, Figure S18), and Fe 2 O 3 /RGO (Supporting Information, Figure S19) based on the following relationship: i p = αv b , where i p and v are peak current and scan rate, respectively, while a and b are variables, with the b ‐value determined from the slope of the plot of log i p versus log v . A b value of 0.5 indicates that the electrochemical process is diffusion‐limited behavior, when b= 1.0, it indicates a surface‐controlled capacitive process . The b value of the S‐H‐Fe 2 O 3 /RGO was calculated to be 0.92 at scan rates from 0.1 to 2 mV s −1 , which is higher than that of the L‐H‐Fe 2 O 3 /RGO (0.85) and the Fe 2 O 3 /RGO (0.71) (Figure c), demonstrating more dominant surface‐controlled kinetics for the S‐H‐Fe 2 O 3 /RGO and in accordance with its remarkable rate performance.…”

A Universal Strategy toward Ultrasmall Hollow Nanostructures with Remarkable Electrochemical Performance

“…TheS -H-Fe 2 O 3 /RGO delivered an excellent rate capability with highly reversible capacities of 1167, 1087, 1012, 936, and 701 mAh g À1 at 0.2, 0.5, 1, 2, and 5Ag À1 , respectively (Figure 5b S19) based on the following relationship: i p = av b ,w here i p and v are peak current and scan rate,r espectively,w hile aa nd b are variables,w ith the b-value determined from the slope of the plot of log i p versus log v. A b value of 0.5 indicates that the electrochemical process is diffusion-limited behavior, when b = 1.0, it indicates as urface-controlled capacitive process. [42][43][44][45][46][47] The b value of the S-H-Fe 2 O 3 /RGO was calculated to be 0.92 at scan rates from 0.1 to 2mVs À1 , which is higher than that of the L-H-Fe 2 O 3 /RGO (0.85) and the Fe 2 O 3 /RGO (0.71) (Figure 5c), demonstrating more dominant surface-controlled kinetics for the S-H-Fe 2 O 3 / RGO and in accordance with its remarkable rate performance.…”