Pomegranate-assisted green synthesis of Cu3Mo2O9 with enhanced Pseudocapacitive performance for energy storage

The significance of this study lies in exploring Cu 3 Mo 2 O 9 as a promising electrode material for high-performance energy storage applications due to its mixed transition metal oxide structure, offering multiple redox-active sites. A novel and eco-friendly green sol-gel method utilizing pomegranate extract as a natural chelating and stabilizing agent was employed for the first time to synthesize Cu 3 Mo 2 O 9 , benefiting from its phytochemical content that enhances gelation and phase formation under mild conditions. XRD analysis confirmed the formation of a single-phase orthorhombic Cu 3 Mo 2 O 9 structure with average crystallite size was 22.3 nm. The optical analysis showed a direct bandgap of 2.39 eV, indicating suitable semiconducting behaviour for pseudocapacitive applications. SEM analysis depicted a porous, agglomerated microstructure with 22 μm grain size, facilitating electrolyte access and charge transport. GCD tests achieved a maximum capacitance of 695 F/g, while CV confirmed pseudocapacitive redox activity through Cu 2+ /Cu + and Mo 6+ /Mo 5+ transitions. EIS revealed low resistance (1.47 Ω) and excellent K + diffusion (Dₖ + = 2.14 × 10 −10 cm 2 /s). This work opens a sustainable route for fabricating multivalent oxide-based electrodes for next-generation hybrid supercapacitors. • Pomegranate extract enabled green sol–gel synthesis of Cu 3 Mo 2 O 9 . • XRD confirms the formation of Cu 3 Mo 2 O 9 . • SEM revealed porous micro-grains (∼22 μm) aiding ion flow. • Capacitance reached 695 F/g with 1.47 Ω resistance. • Bio-assisted route offers eco-friendly energy materials.