Rational Design Hierarchical SnS₂ Uniformly Adhered to Three-Sided Carbon Active Sites to Enhance Sodium Storage

Abstract

Reducing material accumulation and designing reasonable sizes are critical strategies for increasing the rate and cycling stability of electrode materials. Herein, we presented a double-walled hollow carbon spheres (DWHCSs) loading strategy for achieving ultrafine SnS2 nanosheet adhesion by utilizing three-sided active sites of the interior/exterior carbon walls. The structure effectively shortened the electron/ion transport path, increased the effective contact between electrolyte and electrode material, and promoted ion diffusion kinetics. Furthermore, the hollow structure can adapt to the volume change of the electrode during the cycle, preventing active substances from draining. Based on the above advantages, SnS2@DWHCSs as an anode material for sodium ion batteries (SIBs) exhibited a distinguished reversible capacity of 665.7 mA h g–1 at 2 A g–1 after 1000 cycles, and a superior rate ability of 377.6 mA h g–1 at an ultrahigh rate of 10 A g–1. The outstanding electrochemical performance revealed that the structure exhibited a broad application prospect in the field of energy storage and provided a reference for the rational design of other 2D materials.

Recent advances in SnS2-based nanomaterials as high-performance anodes for sodium ion batteries

“…6f). 50 The TEM image in Fig. 6g depicts hollow carbon spheres consisting of two carbon walls with some SnS 2 nanosheets growing uniformly on the inner wall of the outer carbon and the double wall of the inner carbon without aggregation.…”

“…Copyright 2022, reprinted with permission from American Chemical Society. 50 the highest reversible capacity of 631 mA h g −1 at 0.2 A g −1 after 100 cycles, and superior rate capability of 709, 696, 632, 576, and 517 mA h g −1 at 0.1, 0.2, 0.5 and 2 A g −1 , respectively. The excellent electrochemical performance could be attributed to the outer carbon shell providing good electrical conductivity, preventing the aggregation of SnS 2 nanosheets, and offering enough inner void space to accommodate the volume expansion during cycling.…”

“…Wu et al prepared double-walled hollow carbon spheres (DWHCS) and anchored SnS 2 nanosheets on it. 50 Through ex situ XRD at six charge and discharge states, they investigated the sodium storage mechanism of the prepared SnS 2 @DWHCS anode materials (Fig. 3a), and found that the composite experienced three sodium storage processes, as shown in Fig.…”