The pursuit of sustainable technologies for both environmental purification and energy storage has driven the development of multifunctional nanomaterials capable of delivering high performance in diverse applications. In this study, a g-C3N5/MnCo2S4 nanocomposite was successfully fabricated using a simple indirect-hydrothermal method and systematically assessed for its dual functionality in photocatalytic pollutant removal and electrochemical energy storage. Under visible-light irradiation, the composite displayed superior photocatalytic activity toward Congo Red dye, achieving a degradation efficiency of 92.45% within 60 min. In parallel, the material exhibited superior capacitive behavior, delivering a specific capacitance of 1188.57 F g–1 at 1 A g–1 along with long-term cycling stability over 10,000 charge–discharge cycles. Morphological analyses through FE-SEM and HR-TEM indicated a homogeneous integration of MnCo2S4 rock-like structures onto the g-C3N5 layered structures in the nanocomposite, which results in increased surface area, as verified by BET analysis. Impedance measurements confirmed a markedly reduced internal resistance in the nanocomposite, indicating efficient ion transport and improved electrical conductivity compared to their individuals. The fabricated asymmetric device exhibits a high energy density of 22.81 Wh kg–1 at 599.3 W kg–1 power density. Collectively, these findings demonstrate that the g-C3N5/MnCo2S4 nanocomposite is a highly effective, low-cost, multifunctional material with strong potential for synergistic applications in wastewater treatment and energy-storage systems. The work also emphasizes the broader prospects of engineering g-C3N5-based materials for next-generation environmental and energy technologies.
Nehru et al. (Tue,) studied this question.