Ultrathin Nanosheets Assembled Hierarchical Co/NiS_x@C Hollow Spheres for Reversible Lithium Storage

Abstract

Cobalt sulfides are good candidate anode materials for lithium ion storage for their high theoretical capacities. However, their electrochemical performance is restricted by their volume change during the cycles, leading to a sharp capacity fading in the subsequent process. To overcome these disadvantages, ultrathin nanosheets assembled hierarchical cobalt sulfides@C hollow spheres are fabricated by a hydrothermal and subsequent carbon enwrapping strategy. The as-prepared hierarchical Co 9 S 8 @C hollow spheres deliver an enhanced electrochemical performance with both long-term cyclability and reversible specific capacities. 823 mA h g −1 reversible capacity could be maintained after 200 cycles at a current density of 100 mA g −1 . More importantly, the present synthesis strategy shows good generality for the synthesis of nickel sulfide and Ni−Co bimetal sulfides hollow spheres with improved performance in anode materials of lithium ion batteries. KEYWORDS: Co/NiS x @C, hierarchical hollow spheres, ultrathin nanosheets, template method, lithium ion batteries

Ultrafine Co1–xS Attached to Porous Interconnected Carbon Skeleton for Sodium-Ion Batteries

“…The values in Table S2 are used to simulate the resistance of each part before and after the battery cycles. The Rer value decreased from 435.5 Ω to 196.6 Ω cycling, which is mainly due to the infiltration of sodium salts and electrolytes into nanoparticles. , …”

“…The Rer value decreased from 435.5 Ω to 196.6 Ω cycling, which is mainly due to the infiltration of sodium salts and electrolytes into nanoparticles. 56,57 In recent years, reports about the combination of battery and capacitance concept continue to garner excitement, constantly promoting the discovery of new electrode materials or the uncovering of the reaction mechanism. 58 Compared with the diffusion mechanism of traditional batteries, this pseudocapacitance mechanism has been proven to have the characteristics of fast charging and discharging.…”

A Bio‐Inspired Structurally‐Responsive and Polysulfides‐Mobilizable Carbon/Sulfur Composite as Long‐Cycling Life Li−S Battery Cathode

“…The peaks at 399.1, 400.7 and 405.7 eV are ascribed to the pyridinic N, pyrrolic N, and À NO from the adsorbed NO x , respectively. [27] In Figure 5a, we determine the content of sulfur within the composite through thermogravimetric analysis (TGA). The carbon/sulfur composite show an obvious weight loss from 200 to 300°C.…”

“…Figure d shows the high‐resolution spectrum of N 1s. The peaks at 399.1, 400.7 and 405.7 eV are ascribed to the pyridinic N, pyrrolic N, and −NO from the adsorbed NO x , respectively …”

ZIF‐67 Derived Hollow Co9S8 as an Efficient Polysulfides Prohibitor for High Performance Lithium‐Sulfur Batteries

“…Based on the previous strategies, the electrochemical properties of LSBs will be improved to a great extent by using a bi-functional separator coating material with physical entrapment and chemisorption for soluble polysulfides. Some researchers have applied hollow structure cobalt sulfide [35][36][37] to lithium ion batteries, but there are few reports in LSBs. Inspired by these solutions, a novel ZIF-67 derived hollow Co 9 S 8 separator modified coating was applied to LSBs.…”