This study presents a systematic comparison of CuMoO₄ electrodes synthesized using dimethyl sulfoxide (DMSO) and N-methyl-2-pyrrolidone (NMP) as solvent media, with emphasis on their structural and electrochemical performance for supercapacitor applications. Both solvents enable the formation of crystalline CuMoO₄; however, distinct differences in morphology and electrochemical behavior are observed. The DMSO-derived electrode exhibits a more porous and homogeneous structure, facilitating enhanced electrolyte accessibility and ion transport. As a result, it delivers a high specific capacitance of 549.6 F g⁻¹ at 1 A g⁻¹, significantly outperforming the NMP-based electrode (266 F g⁻¹ at 1 A g⁻¹). Even at elevated current densities, the DMSO electrode maintains a capacitance of 323 F g⁻¹ at 20 A g⁻¹, indicating superior rate capability.Electrochemical impedance spectroscopy reveals reduced charge transfer resistance and improved ion diffusion kinetics for the DMSO-derived electrode, which is attributed to improved electrode architecture and enhanced electronic pathways. Furthermore, the DMSO-based system demonstrates better cycling stability compared to the NMP counterpart, maintaining consistent electrochemical performance over repeated cycles. The comparable voltage windows observed in cyclic voltammetry and galvanostatic charge–discharge profiles confirm stable operation, while the improved performance is linked to more efficient utilization of electroactive sites.The findings demonstrate that solvent selection plays a decisive role in tailoring the structural and electrochemical properties of CuMoO₄ electrodes. DMSO-assisted synthesis enables the formation of a more favorable electrode architecture, resulting in enhanced capacitance, rate capability, and stability. This study highlights solvent engineering as an effective strategy for optimizing electrode materials in advanced supercapacitor systems.
Şahmetlioğlu et al. (2025) studied this question.