Designed Tetranuclear Iron-oxo Clusters with Redox Activity for High-Performance Lithium Storage

Area of Science:

• Materials Science
• Electrochemistry
• Inorganic Chemistry

Background:

• Polyoxometalates (POMs) show potential for energy storage due to redox activity.
• Eco-friendly iron-oxo clusters with unique structures are underexplored for lithium-ion storage.

Purpose of the Study:

• Synthesize novel redox-active tetranuclear iron-oxo clusters.
• Evaluate their performance as anode materials for lithium-ion batteries.

Main Methods:

• Solvothermal synthesis with varying Fe3+ and SO4 2- ratios.
• Electrochemical testing of synthesized clusters as anode materials.

Main Results:

• Three novel tetranuclear iron-oxo clusters were successfully synthesized.
• Cluster H6 [Fe4 O2 (H2 O)2 (SO4 )7 ]⋅H2 O demonstrated a discharge capacity of 1784 mAh g−1 at 0.2 C.
• This cluster exhibited good cycle performance, marking the first use of inorganic iron-oxo clusters for Li-ion storage.

Conclusions:

• Inorganic iron-oxo clusters can function as effective anode materials for Li-ion batteries.
• The unique 1D pore structure in H6 [Fe4 O2 (H2 O)2 (SO4 )7 ]⋅H2 O contributes to its electrochemical performance.
• This work establishes a new molecular model for studying iron-oxo clusters in energy storage applications.