Hydrothermal synthesis of ceria oxide nanorod decorated on manganese doped molybdenum disulfide nanoflowers for asymmetric supercapacitor performance

A novel composite of manganese doped molybdenum sulfide (Mn-MoS₂) nanoflowers coated with ceria oxide (CeO₂) nanorods (Mn-MoS₂/CeO₂) nanocomposites was successfully prepared using a hydrothermal synthesis route. Scanning electron microscopy (SEM) analysis showed flower-like Mn-MoS₂ nanosheets uniformly decorated with CeO₂ nanorods, creating a hierarchical structure that improved electrolyte accessibility and charge storage. The addition of CeO₂ increased the specific surface area from 20.48 to 25.53 m² g⁻¹ and boosted the specific capacitance from 64.4 to 158.5 F g⁻¹ at 5 mV s⁻¹ in a three electrode system using 1 M Li₂SO₄ electrolyte. An asymmetric supercapacitor composed of Mn-MoS₂/CeO₂ and nitrogen doped reduce graphene oxide (N-rGO) achieved a specific energy density of 24.8 Wh kg⁻¹ and a specific power density of 525.6 W kg⁻¹ , maintaining 89% of its initial capacitance after 12,000 cycles. This study confirms that the Mn-MoS₂/CeO₂ composite shows great potential for next-generation asymmetric SCs, offering an efficient approach to boost the energy storage capacity of manganese-doped nanomaterials.