Solvothermal synthesis of Ni doped Mn2Se3 Nanomaterial (NiMn2Se3) as an electrode for supercapacitor applications
摘要
NiMn2Se3 nanomaterials were synthesized successfully via a solvothermal method employing nickel acetate tetrahydrate, manganese acetate tetrahydrate, selenium dioxide, and triethanolamine (TEA) as a complexing agent. X-ray diffraction analysis confirmed the formation of a polycrystalline structure with an average crystallite size of 50 nm. X-ray photoelectron spectroscopy verified the presence of Mn2+, Ni2+, and Se2− oxidation states, confirming the effective incorporation of constituent elements. FTIR spectra revealed characteristic metal–oxygen bonding and functional groups, supporting the formation of the targeted nanostructure. Optical studies demonstrated a direct bandgap of 1.52 eV, indicating semiconducting behaviour suitable for energy-storage and optoelectronic applications. The transmittance characteristics showed low ultraviolet, moderate visible, and high infrared transmittance, further supporting multifunctional applicability. FESEM analysis revealed a mixed morphology of rods, needles, and sheet-like structures, which significantly enhanced surface area and electrochemical accessibility. Elemental composition and uniformity were confirmed by EDS analysis. Electrochemical evaluation in a 0.1 M KOH electrolyte demonstrated excellent capacitive behaviour, delivering high specific capacitance values of 529, 98, 48, and 3 F g−1 at scan rates of 5, 10, 20, and 100 mV s−1, respectively. Remarkably, the electrode exhibited a capacitive retention of 112% after prolonged cycling, indicating outstanding stability. A high electrochemically active surface area of 3.6795 cm2, along with an energy density of 0.84 Wh kg−1 and power density of 17.38 W kg−1, highlights efficient charge storage and transfer. Overall, the results establish NiMn2Se3 as a durable and high-performance electrode material for advanced supercapacitor applications.