One-pot hydrothermal synthesis of MgV₂O₅-NC porous composite for hybrid supercapacitors with enhanced storage properties

A facile and scalable method is reported for MgV₂O₅ (MVO) interconnected with a porous nitrogen-doped carbon (NC) sphere network using a hydrothermal technique. The synthesized MgV₂O₅-N-doped Carbon (MVO-NC) nanocomposite has an orthorhombic crystal plane and a sheet-like MVO with a porous NC network based on structural and morphological analyses. In an aqueous electrolyte, the hydrothermally produced MVO-NC electrode demonstrates good charge–discharge performance, with an exceptional cycling retention of 97.05% over 5000 cycles. At 2 A g⁻¹, the MVO-NC has a higher specific capacitance of 358 F g⁻¹ than other MVO electrode compositions (272 F g⁻¹) and V₂O₅ (146 F g⁻¹). Owing to the highly redox-active MVO-NC composite and exceptionally porous activated carbon components, the hybrid supercapacitors achieve a maximum energy density of 38 W h kg⁻¹ and maximum power density of 8000 W kg⁻¹. The two-dimensional porous network structure of the MVO, along with the porous NC, creates sufficient interstitial space for electrolyte accommodation, thereby allowing a rapid and reversible electrochemical process.