Efficient electrochemical hydrogen evolution and congo red degradation using FeCeMg nanometal oxide/hydroxide catalyst supported on biomass-derived carbon sheet

The development of highly efficient and economically viable catalysts is key for advancing sustainable energy harvesting and environmental remediation to address future global demands. In this study, hybrid FeCeMg-SH (Sargassum horneri-derived) nanocomposites were synthesized via a one-step hydrothermal approach towards multi-application for electrochemical water splitting and dye degradation. At 1st place the fabricated nanocomposites exhibited cuboidal morphologies organized into elongated dendritic architectures. In alkaline solution, the catalyst showed superior oxygen evolution reaction (OER) (j₁₀₀/₃₀₀ = 223.6/339.5 mV) and hydrogen evolution reaction (HER) (j₁₀₀/₃₀₀ = 127.8/226.3 mV). In a two-electrode configuration (2-E), the hybrid catalyst achieved an overpotential of 1.88 V at 300 mA/cm2, surpassing the benchmark Pt/C‖RuO₂ electrode, which required 1.91 V Vs. RHE under identical conditions. The long-term stability of the FeCeMg-SH nanocomposite was confirmed through chronoamperometric measurements over 12 h, with durability was further analyzed using a long short-term memory (LSTM) statistical approach. Further, the hybrid nanocomposite was employed in environmental remediation application, achieving a Congo Red (CR) dye degradation efficiency of approximately 99.7% within 50 min. The material retained high performance across 6 recycling cycles, highlighting its robustness. Density functional theory (DFT) studies were employed to elucidate the underlying mechanism of CR dye degradation, providing valuable insights into the nanocomposite's catalytic activity. These results position FeCeMg-SH as a promising material for integrated applications in sustainable energy technologies and environmental cleanup.