Search

WO-2026095928-A1 - SULFUR MATERIAL CONTAINING QUANTUM DOT COMPONENT, METHOD FOR PRODUCING THE SULFUR MATERIAL, ELECTRODE, AND LITHIUM-SULFUR BATTERY

WO2026095928A1WO 2026095928 A1WO2026095928 A1WO 2026095928A1WO-2026095928-A1

Abstract

A material may include sulfur and a quantum dot component. The quantum dot component may be a quantum dot-nanotube composite, a quantum dot-graphene composite, carbon quantum dots consisting essentially of carbon, hybrid quantum dots comprising carbon and at least one metal oxide, or any combination. A method of making the material may involve making the quantum dot component by a sol-gel process and combining the quantum dot component with the sulfur. The material may serve as a cathode material for a battery, particularly a lithium-sulfur battery. The lithium-sulfur battery may overcome or partially overcome the shuttle effect.

Inventors

  • CZUBAROW, PAWEL
  • LU, ZHIXIANG
  • KRASCO, NICHOLAS CHARLES
  • ROTHFUSS, Arianna

Assignees

  • NAMICS CORPORATION

Dates

Publication Date
20260507
Application Date
20241030

Claims (20)

  1. 1. A material, comprising: sulfur, and a quantum dot component, wherein the quantum dot component is at least one component selected from the group consisting of: a quantum dot-nanotube composite, a quantum dot-graphene composite, carbon quantum dots consisting essentially of carbon, and hybrid quantum dots comprising carbon and at least one metal oxide.
  2. 2. The material of claim 1, wherein the quantum dot component comprises the quantum dot-nanotube composite.
  3. 3. The material of claim 2, wherein the quantum dot-nanotube composite comprises a plurality of nanotube portions, and wherein the quantum dot-nanotube composite further comprises a plurality of quantum dot portions along a length of each nanotube portion.
  4. 4. The material of claim 3, wherein quantum dot portions of the plurality of quantum dot portions have a number average particle diameter of from 5 to 40 nm.
  5. 5. The material of claim 1 , wherein the quantum dot component is obtained by subjecting a mixture to a sol-gel process, the mixture comprising a carbon source, a solvent, optionally a metal oxide precursor, optionally nanotubes, and optionally graphene.
  6. 6. The material of claim 5, wherein the mixture comprises an alkoxide of at least one metal as the metal oxide precursor.
  7. 7. The material of claim 1, wherein the sulfur comprises octasulfur Sx and/or elemental sulfur.
  8. 8. The material of claim 2, wherein the quantum dot-nanotube composite consists essentially of carbon.
  9. 9. The material of claim 1, wherein the quantum dot component comprises the quantum dot-nanotube composite, the hybrid quantum dots, or both, and wherein the quantum dot-nanotube composite, the hybrid quantum dots, or both comprise carbon and a metal oxide.
  10. 10. The material of claim 9, wherein the metal oxide comprises at least one oxide of a transition metal.
  11. 11. The material of claim 9, wherein the metal oxide comprises an oxide of at least one metal or metalloid selected from the group consisting of tungsten, molybdenum, ruthenium, niobium, tantalum, germanium, iron, silver, manganese, titanium, tin, antimony, bismuth, gold, silicon, nickel, cobalt, chromium, zirconium, and vanadium.
  12. 12. The material of claim 9, wherein the metal oxide comprises an oxide of tungsten or molybdenum.
  13. 13. The material of claim 9, wherein the metal oxide comprises a tungsten oxide.
  14. 14. The material of claim 9, wherein the quantum dot component comprises the quantum dot-nanotube composite, and wherein the quantum dot-nanotube composite has a carbon content of from 90% to 99.9% by mass and a total content of the at least one metal oxide of from 0.1% to 2% by mass, based on a total mass of the quantum dot-nanotube composite.
  15. 15. The material of claim 1, wherein the sulfur is mixed with the quantum dot component on a nanometer scale.
  16. 16. The material of claim 1, wherein a quantum dot component content is from 5% to 40% by mass, based on a total mass of the material.
  17. 17. The material of claim 2, wherein nanotubes constituting the carbon dot-nanotube composite are carbon nanotubes.
  18. 18. The material of claim 2, wherein nanotubes constituting the carbon dot-nanotube composite are single wall carbon nanotubes.
  19. 19. The material of claim 5, wherein the mixture comprises from 0.1 to 20% by mass of the carbon source, from 0.10% to 5.0% by mass of the nanotubes, from 60% to 95% by mass of the solvent, and from 0 to 20% by mass of the metal oxide precursor.
  20. 20. The material of claim 1, further comprising carbon black.

Description

TITLE SULFUR MATERIAL CONTAINING QUANTUM DOT COMPONENT, METHOD FOR PRODUCING THE SULFUR MATERIAL, ELECTRODE, AND LITHIUM- SULFUR BATTERY BACKGROUND Technical Field The present disclosure relates to a material that includes sulfur and a quantum dot component. The material may be used in electrochemical energy storage devices, in particular as an electrode in batteries such as lithium-sulfur batteries. The present disclosure further relates to improvements in the composition and function of batteries such as lithium-sulfur batteries, with respect to mitigating the shuttle effect. Background Art Rechargeable lithium-sulfur batteries may have certain advantages in terms of cost-effectiveness, capacity, and relatively low weight resulting from lower density materials. Lithium-sulfur batteries have high theoretical capacity of about 1672 mAh/g, and high theoretical energy density of about 2600 Wh/kg. These advantages may render lithium-sulfur batteries more desirable in some respects than lithium-ion batteries. However, performance in lithium-sulfur batteries may suffer over time and/or after several charge-discharge cycles, due to the shuttle effect. Lithium-sulfur batteries involve a metallic lithium anode and a sulfur (Ss) cathode. As the battery discharges, lithium from the lithium anode produces lithium ions and electrons. The lithium ions then react with the sulfur in the cathode to produce lithium sulfide (LiiS). In the formation of the lithium sulfide during discharge, lithium poly sulfides (Li2Ss, Li2Se, Li2S4, Li2S2) form as intermediates. These polysulfides may be soluble in the electrolyte, which may move from the cathode into the electrolyte and to the lithium anode, where they may form shorter polysulfides. The shorter polysulfides may then move back to the cathode to again form longer poly sulfides. This movement and reaction of the poly sulfides between the anode and the cathode depletes the capacity of the battery. Such depletion of lithium-sulfur battery capacity by formation and movement of poly sulfides may be referred to as the “shuttle effect.” Inclusion of nanostructures may have represented other attempts to mitigate the shuttle effect or to obtain other benefits in lithium sulfur batteries or in other batteries. However, inasmuch as such attempts have failed to include a quantum dot component as disclosed herein, they have accordingly failed to provide sufficient mitigation of the shuttle effect in a lithium sulfur battery. For example, the cathode may have incorporated nanotubes or nanoporous, microporous, or mesoporous carbon, (see Li et al., “Engineering Strategies for Suppressing the Shuttle Effect in Lithium-Sulfur Batteries” Nano-Micro Lett. (2024) 16:12, published online November 10, 2023, incorporated herein by reference). In CN109494346B, incorporated herein by reference, the cathode may have incorporated functionalized quantum dots such as polyethyleneimine- functionalized quantum dots, for an absorption effect of the polyethyleneimine on poly sulfide. CN108417893B, incorporated herein by reference, may have used carbon quantum dots containing nitrogen or oxygen elements with strong polarity or boron, sulfur, and phosphorous elements, in an attempt to provide a chemical adsorption effect on lithium in lithium polysulfide molecules. In CN11134200 IB, incorporated herein by reference, the cathode may have incorporated other functionalized carbon quantum dots or other nanomaterials entirely, nanometer oxide, nanometer carbide (for example tungsten carbide or titanium carbide), nanometer nitride (for example tungsten nitride), nanometer sulfide. CN10678485 IB, incorporated herein by reference, may have included graphene quantum dots, formed in a bottom-up fashion of stacking graphene layers, rather than a cohesive, bonded material as in a carbon quantum dot. KR101884870B1, incorporated herein by reference, may have included graphene quantum dots and/or carbon black particles, but not carbon quantum dots. In CN10678485 IB, incorporated herein by reference, the cathode may have incorporated titanium nitride and/or titanium di oxi de-titanium nitride quantum dots. In CN106784851B, incorporated herein by reference, the cathode may have incorporated zinc sulfide quantum dots with carbon nanotubes. In still other possibilities, in an attempt to mitigate the shuttle effect, the electrolyte may have incorporated one or more additives, for example ammonia modified carbon quantum dots as in CN110518285B, incorporated herein by reference, or graphene quantum dots as in CN110504488B, incorporated herein by reference. In yet other possibilities, the lithium anode may have incorporated one or more additives, for example graphene quantum dots, as in CN110504451B, incorporated herein by reference. Even with such measures for adding nanomaterials or other materials to the cathode or to the electrolyte, reduction or further reduction of the shuttle effect has still been needed. Furthermore, conce