Nano Sn₂S₃ Embedded in Nitrogenous‐Carbon Compounds for Long‐Life and High‐Rate Cycling Sodium‐Ion Batteries

Abstract

Metallic tin (Sn) compounds are viewed as promising candidates for sodium-ion batteries (SIB) anode materials yet suffer from large volume expansion and limited electrode kinetics. Manufacturing rational structure is a crucial factor to achieve high-efficiency sodium storage for SIBs. In this study, nano Sn 2 S 3 embedded in nitrogenous-carbon compounds (nano-Sn 2 S 3 /C) was designed for SIB anode materials via a facile three-step strategy: precipitation, heat treatment and vulcanization with no templating agent. Density functional theory calculations suggested that Sn 2 S 3 displayed a low Na + diffusion energy barrier and the SnÀ S bonds could be rebuilt during the sodiation/de-sodiation process. Notably, electrochemical measurements coupled with ex-situ X-ray diffraction and ex-situ transmission electron microscopy were proposed to reveal the underlying Na + storage mechanisms. Sn 2 S 3 acted as a highcapacity composition, while the porous nitrogenous-carbon matrix served as a rigid-conductive frame to accommodate the volume expansion and prevented the aggregation of nano Sn 2 S 3 . The rationally generated architectures benefited greatly in rate capacity and structural stability. As expected, the asprepared nano Sn 2 S 3 /C exhibited remarkable rate capabilities with a specific capacity of 603 and 160 mAh g À 1 under typical conditions at 0.2 and 4 A g À 1 , respectively. This work may trigger new enthusiasm for engineering high-performance SIB anode materials.

Polycrystalline Fe- and Sn-based sulfides for high-capacity sodium-ion battery anodes

“…S13). According to the recently reported results for Sn 2 S 3 /C, 14 FeS/C, 15 Fe 7 S 8 /C, 16 SnS 2 /C, 17 and Fig. S13 (ESI †), the initial CV curve of FSS/G-15% showed a certain degree of irreversibility because of the side reactions including formation of a solid interface electrolyte membrane and the irreversible adsorption of Na + in micropores.…”

“…S13 (ESI †), the initial CV curve of FSS/G-15% showed a certain degree of irreversibility because of the side reactions including formation of a solid interface electrolyte membrane and the irreversible adsorption of Na + in micropores. 10,[14][15][16] From the 2nd to 5th cycles, the redox peaks located at 0.23/0.13, 0.73/0.33-0.37, and 1.14/0.92 V were due to muti-step alloy/de-alloy reactions between Na and Sn, those at 1.38/0.62 V were due to the reversible reaction of Na with FeS/Fe 7 S 8 , and those at 1.67/ 1.02 and 2.04/1.62 V were due to muti-step reactions of Na When using FSS, some redox peaks merged and vanished (Fig. S14, ESI †), illustrating less reversibility.…”

“…S13 (ESI†), the initial CV curve of FSS/G-15% showed a certain degree of irreversibility because of the side reactions including formation of a solid interface electrolyte membrane and the irreversible adsorption of Na + in micropores. 10,14–16 From the 2nd to 5th cycles, the redox peaks located at 0.23/0.13, 0.73/0.33–0.37, and 1.14/0.92 V were due to muti-step alloy/de-alloy reactions between Na and Sn, those at 1.38/0.62 V were due to the reversible reaction of Na with FeS/Fe 7 S 8 , and those at 1.67/1.02 and 2.04/1.62 V were due to muti-step reactions of Na 3.75 Sn with Na 2 S. These reactions can be written using the equations0.23/0.05 V: Sn + x 1 Na ⇔ Na x 1 Sn0.73/0.33–0.37 V: Na x 1 Sn + x 2 Na ⇔ Na x 1 + x 2 Sn1.14/0.92 V: Na x 1 + x 2 Sn + x 3 Na ⇔ Na 3.75 Sn1.38/0.62 V: Na 2 S + Fe ⇔ FeS + 2Na,and 8/7Na 2 S + Fe⇔ 1/7Fe 7 S 8 + 16/7Na1.67/1.02 V: (3 − ε )/2 Na 2 S + Na 3.75 Sn ⇔ 1/2 Sn 2 S 3− ε + (6.75 − ε)Na,and (4 − ξ )/3 Na 2 S + Na 3.75 Sn ⇔ 1/3 Sn 3 S 4− ξ + (77/12 − 2/3 ξ )Na2.04/1.62 V: Sn 2 S 3− ε + ε Na 2 S ⇔ Sn 2 S 3 + 2 ε Na,and 4/3 Na 2 S + Na 3.75 Sn ⇔ 1/3 Sn 3 S 4 + 77/12 Na…”

Confining Nano-GeS2 in Cross-Linked Porous Carbon Networks for High-Performance and Flexible Li-Ion Battery Anodes

“…Moreover, the rate cycle performance of GeS 2 /C-2 was investigated, and the results under various current densities (0.1–4.0 A g –1 ) are presented in Figure c, GeS 2 /C-2 delivered a reversible capacity of about 585 mA h g –1 when the current density further changed to 0.2 A g –1 , suggesting the good rate cycle performance of GeS 2 /C-2. The performance of GeS 2 /C-2 was also compared with reported chalcogenides in the literatures, − as shown in Figure d. GeS 2 /C-2 showed one of the best performances compared to chalcogenides, such as high reversible capacity of discharge/charge at 0.1 A g –1 or high reversible capacity of rate cycles.…”

SnS2 Nanosheets with RGO Modification as High-Performance Anode Materials for Na-Ion and K-Ion Batteries

“…Specifically, the hexagonal tin (IV) sulfide (SnS 2 ) possesses unique two-dimensional (2D) layered structure with large interlayer spacing and high specific capacity based on both conversion and alloying processes [ 9 , 10 , 11 ], which makes it more appropriate for Na-ion and K-ion storage. Unfortunately, similar to other TMSs, SnS 2 also has the low intrinsic conductivity and the dramatic volume and structural changes, which will easily lead to the poor sluggish kinetics and rapid capacity reduction in the process of Na + and K + insertion/extraction [ 12 , 13 , 14 , 15 ].…”