Investigation on synthesis and characterization of pyramidal shaped transition metals chalcogenide novel molybdenum nickel selenide (MoNiSe 4 ) nanomaterial and enhanced electrochemical performance of the electrode for supercapacitor applications

Abstract The novel pyramidal-shaped ternary molybdenum nickel selenide (MoNiSe 4 ) nanomaterial was successfully synthesized using a solvothermal technique for the first time. The structural, optical and electrochemical properties of the synthesized sample were analyzed through XPS, XRD, UV–visible spectroscopy, Fourier Transform infrared (FTIR), field emission scanning electron microscope (FESEM) and EDX analyses. The XRD pattern revealed a distinct shift of the main diffraction peaks toward lower angle side compared to pure MoSe 3 , validating the effective incorporation of nickel and the formation of the MoNiSe 4 phase with an average crystallite size of 44 nm. The optical band gap of the material was estimated as 1.41 eV. FTIR spectra confirmed the presence of relevant metal–selenide bonds and its functional groups. Morphological analysis by FESEM revealed a pyramidal shape with triangular surfaces featuring sharp edges and distinct facets that reflect its high crystallinity. Elemental analysis through energy dispersive x-ray spectroscopy validated the stoichiometric composition of Mo, Ni and Se, whereas XPS analysis confirmed the oxidation states as Mo 6+ , Ni 2+ and Se 2− , further supporting the formation of the MoNiSe 4 phase. Electrochemical analysis demonstrated superior supercapacitive characteristics of the MoNiSe 4 electrode. Cyclic voltammetry exhibited a pseudocapacitive nature with specific capacitances of 304 F g −1 and 161 F g −1 at the scan rates of 50 and 100 mV s −1 respectively. Galvanostatic charge–discharge studies showed remarkable cycling stability with good capacitance retention even after 1500 cycles. The calculated specific capacitance, energy density and power density after 1500 cycles were 5695 × 10 −5 F g −1 , 285 × 10 −9 Wh kg −1 and 24 × 10 −3 W kg −1 respectively. The Nyquist and Bode plots indicated ideal capacitive and pseudocapacitive behavior, confirming the efficient charge storage performance of the electrode. Overall, the MoNiSe 4 demonstrates strong potential as a highly effective electrode material for advanced supercapacitor applications.