In-situ Formation of a Series of AgFeO₂/γ-Fe₂O₃ Composites: Impact on Electrochemical Performance

A paradigm for the synthetic manipulation of composition and crystallite size of bimetallic composites via a low-temperature, aqueous co-precipitation technique employing non-stoichiometric ratios of starting materials, AgNO3 and Fe(NO3)3, is introduced. In-situ formation of composites containing crystalline silver ferrite, AgFeO2, and nanocrystalline maghemite, γ-Fe2O3 is demonstrated and established by Raman spectroscopic and X-ray absorption analyses. As a cathode, the lowest silver content composites exhibited profoundly improved electrochemical performance, with reversible capacities approximately 100% higher relative to stoichiometric AgFeO2, and demonstrate the lowest capacity fade.