Enhanced energy storage efficiency with NbSnMoS2 nanosheets as electrode material in hybrid supercapacitor devices

Abstract

NbSnMoS₂ material with an enhanced extrinsic nature was synthesized using the hydrothermal method and employed as an electrode for hybrid supercapacitor application (HSC). X-ray diffraction pattern confirmed the hexagonal crystal structure formation in NbSnMoS₂ material. A morphology with nanosheets, along with clustered nanoparticles, was identified in NbSnMoS₂ using field emission scanning electron microscopy. The presence of Nb^4+/5+, Sn⁴⁺, Mo⁴⁺, S²⁻, and O²⁻ compositional states in NbSnMoS₂ was confirmed through X-ray photoelectron spectroscopy. The electrochemical three-electrode system benefited from the intensified van der Waals interaction and enriched sulfur-edged active sites, therefore, a high specific capacitance of 536.2 F g⁻¹ at 1 A g⁻¹ was gained by the NbSnMoS₂ electrode. The facile ion transport pathway was enhanced by the smooth electrode/electrolyte interface formation, whereby the constructed NbSnMoS₂//AC HSC device showed energy and power density of 25.04 W h kg⁻¹ and 800 W kg⁻¹. The HSC device retained 99.21 and 93.99% of its coulombic efficiency and capacity retention for 10 000 cycles. The results prove that NbSnMoS₂ is a novel material for the development of commercial supercapacitors.