Facile Synthesis of FeS₂ Quantum‐Dots/Functionalized Graphene‐Sheet Composites as Advanced Anode Material for Sodium‐ion Batteries

Abstract

FeS2 quantum‐dots/functionalized graphene‐sheet (QDs/FGS) composites are prepared by a facile and scalable method. The FeS2 QDs/FGS composites can be used as anode materials for sodium‐ion batteries. The FeS2 QDs/FGS composites can achieve large specific discharge and charge capacities of 742 and 683 mAh•g−1 (based on the total mass of the FeS2 QDs/FGS composites) at the current density of 0.5 A•g−1 in the first cycle, respectively, and retain a reversible charge capacity of 552 mAh•g−1 after 100 cycles. The FeS2 QDs/FGS composites can display high specific capacities of 452 and 315 mAh•g−1 at the high current densities of 2 and 5 A•g−1. These results indicate that the FeS2 QDs/FGS composites have good cycle performance and high rate capability, making them promising candidates as anode material for sodium‐ion batteries.

Na‐Doped C70 Fullerene/N‐Doped Graphene/Fe‐Based Quantum Dot Nanocomposites for Sodium‐Ion Batteries with Ultrahigh Coulombic Efficiency

“…The peak at 0.5 V is the reduction peak of FeS 2 ,,. And most striking, the CV curve is still in its original form in the subsequent 300 cycles although the three small peaks disappeared due to decomposition reactions of Fe 2 O 3 and FeS 2 nanoparticles ,. This results demonstrates the surprising cycling stability, in keeping with the results of Figure d.…”

“…To develop high performance anode materials for SIBs, Fe‐based materials, such as FeNb 11 O 29 , Fe 2 O 3 , Fe 3 O 4 , FeS 2 , and FeS, and Fe 1‐x S, have been extensively studied because of their high theoretical capacities, low cost, earth‐abundance and nontoxicity. Among them, Fe 2 O 3 and FeS 2 have been considered as promising candidates for SIBs.…”

“…synthesized three‐dimensional (3D) porous γ‐Fe 2 O 3 @C nanocomposite by using an aerosol spray pyrolysis technology, in the nanocomposite the γ‐Fe 2 O 3 nanoparticles (5 nm) uniformly embedded in a porous carbon matrix, which shows high‐rate capability and long‐term cyclability when applied as an anode material for SIBs. Yiben Shao et al . prepared FeS 2 quantum‐dots/functionalized graphene‐sheet (QDs/FGS) composites by a facile and scalable method, which were used as anode materials for SIBs and achieved large specific discharge capacities of 742 mAh g −1 at the current density of 0.5 A g −1 in the first cycle, retained a reversible charge capacity of 552 mAh g −1 after 100 cycles and displayed a high specific capacity of 315 mAh g −1 at the high current densities of 5 A g −1 .…”

Ultrafast and Ultrastable Heteroarchitectured Porous Nanocube Anode Composed of CuS/FeS2 Embedded in Nitrogen‐Doped Carbon for Use in Sodium‐Ion Batteries

“…Previous efforts to improve the electrochemical characteristics of FeS 2 have mainly focused on designing nanostructured composites with bifunctional carbon‐based materials that offer high conductivity and serve as a structure‐reinforcing buffer matrix against significant volume variation upon cycling. [ 21,22 ] For example, Chen et al demonstrated that an FeS 2 /carbon nanotube neural network exhibited enhanced cycling stability with a reversible capacity of 394 mAh g –1 after 400 cycles at 200 mA g –1 . [ 14 ] Yin et al prepared FeS 2 @porous octahedral carbon derived from a metal‐organic framework, which showed an excellent rate capability of up to 5000 mA g –1 and good cycle performance.…”