Electrochemical Performance of SnS@Graphene Composites Prepared by Deep Eutectic Solvent Method

Abstract

SnS material is considered as an attractive anode material to substitute commercial graphite anodes of lithium‐ion batteries (LIBs) due to its large capacity, low cost, and environment‐friendliness. However, the side reactions induced during charge/discharge processes significantly expand the volume of SnS material, limiting its development. Herein, a novel deep eutectic solvent is synthesized with polyethylene glycol and SnCl2·2H2O, and SnS@graphene composites are prepared using a one‐step pyrolytic vulcanization method. The composite material is sandwich‐shaped with graphene sheet layers interspersed with SnS particles. Tests after making them into button cells have shown that the composite electrodes have excellent electrochemical properties: an initial discharge capacity of 1346 mAh g−1 at the current density of 100 mA g−1; outstanding long‐period performance under high current. In the case of 1 A g−1, it still has 421.8 mAh g−1 capacity after 1000 cycles. It also shows superior rate characteristics: under the current density of 5 A g−1, its specific discharge capacity is 343 mAh g−1; the specific discharge capacity increases rapidly to 798 mAh g−1 when the current density returns to 1 A g−1.

Exploring the Potential of Carbonized Nano-Si within G@C@Si Anodes for Lithium-Ion Rechargeable Batteries

“…The TG curve reveals three discernible weight loss stages, while the DTG curve presents two primary peaks corresponding to the endothermic transitions. The initial stage shows a weight loss of about 4% between 40 to 165 °C, mainly attributed to the evaporation of moisture in the sample . The subsequent weight loss of around 15.3% during the second and third stages, from 165 to 460 °C, relates to the decomposition of citric acid, resulting in the creation of pyrolyzed carbon.…”

“…The initial stage shows a weight loss of about 4% between 40 to 165 °C, mainly attributed to the evaporation of moisture in the sample. 33 The subsequent weight loss of around 15.3% during the second and third stages, from 165 to 460 °C, relates to the decomposition of citric acid, resulting in the creation of pyrolyzed carbon. Two distinct endothermic peaks appear on the DTG curves at 192 and 355 °C.…”