Spin-Orchestrated Lithium Diffusion in Reforged Ferromagnetic Fe@C Anodes.

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Developing sustainable energy storage solutions is critical.
• Repurposing materials from one application to another can improve resource efficiency.
• Iron-based catalysts are used for methane pyrolysis to produce hydrogen.

Purpose of the Study:

• To investigate the direct repurposing of iron catalysts used in methane pyrolysis as anode materials for lithium-ion batteries.
• To evaluate the electrochemical performance of in situ carbon-coated iron composites (Fe@C900) as battery anodes.
• To explore the effect of magnetic fields on the performance of these novel anodes.

Main Methods:

• Methane pyrolysis at 900 °C to create Fe@C900 composite materials.
• Electrochemical testing of Fe@C900 as a battery anode without conductive additives.
• Application of a 5000 G magnetic field during battery cycling.
• Multimodal characterization and Density Functional Theory (DFT) calculations.

Main Results:

• Fe@C900 composite exhibits a reversible capacity of 380 mAh g⁻¹ with 98% retention over 1000 cycles.
• Magnetic field application enhances rate performance by 150% through spin-guided lithium-ion migration.
• Accelerated lithium kinetics, stable solid electrolyte interphase (SEI) formation, and deep lithiation were observed.
• DFT calculations confirm strong lithium adsorption and low insertion barriers.

Conclusions:

• A novel class of hydrogen-derived ferromagnetic anodes has been introduced.
• The Fe@C900 composite serves as a high-rate, conductor-free lithium storage platform.
• This strategy integrates hydrogen generation with energy storage, offering a scalable path to carbon-efficient, magnetically enhanced battery systems.