Electrochemical capacitive performance of solution-processed αFe2O3-MoSe2 composite in Na2SO3-KOH mixed electrolyte

Hematite (αFe₂O₃) and flower-like molybdenum diselenide (MoSe₂) nanoparticles were synthesized via a simple solution-based process involving an initial hydrothermal/solvothermal step to fabricate precursors, followed by heat treatment to form nanoporous structures with high specific surface areas. The resulting αFe₂O₃ and MoSe₂ powders were uniformly mixed, treated with water, and dried to produce the composite material. The morphology and grain size of the αFe₂O₃-MoSe₂ composite remained unchanged after the treatment, and the material retained distinct crystalline phases of both αFe₂O₃ and MoSe₂. The electrochemical performance of αFe₂O₃, MoSe₂, and the αFe₂O₃-MoSe₂ composite was evaluated in aqueous Na₂SO₃, KOH, and mixed electrolyte solutions. Compared with electrodes made solely from αFe₂O₃ or MoSe₂ in Na₂SO₃ and KOH electrolytes, the composite electrode exhibited enhanced capacitive performance, which achieves a specific capacitance (C_cdc) of 236.9 F·g⁻¹ at a current density of 2.5 mA·cm⁻², along with excellent cycling stability 74.7 % of its initial capacitance after 2000 charge/discharge cycles.