Facile fabrication of Sulfur-Doped CuCr₂O₄ Nanocatalysts: For enhanced bifunctional oxygen and hydrogen evolution reactions

Fossil fuels dominate the energy sector but they are facing sharp decline in their reservoirs and pose severe threats to global climate. Therefore, hydrogen has gained attention for its potential in energy solutions across various sectors. Here in present work, we fabricated S-CuCr₂O₄ at various temperature via hydrothermal method, and then employed for various characterizations to confirm the structural, morphological, and elemental analysis. The S-CuCr₂O₄ shows the morphology like nanosheets with increasing the duration for hydrothermal process for S-CuCr₂O₄-3. Thus, this study emphasizes the importance of sulfur doping and tailoring the electrocatalytic properties of CuCr₂O₄ for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), presenting a stable and a productive dual-functioning catalyst for water splitting. The electrochemical OER activity of S-CuCr₂O₄-3 exhibits the best catalytic activity with an onset potential of 146 mV with the lowest overpotential of 230 mV at 10 mA cm⁻² having a Tafel slope of 49 mVdec⁻¹ for OER. The durability test is performed via chronoamperometry demonstrate the good stability of S-CuCr₂O₄-3. Additionally, the electrochemical HER activity of S-CuCr₂O₄-3 is also examined, and exhibiting an onset potential of 90 mV having overpotential of 251 mV, showing significantly better performance compared to pure CuCr₂O₄. Hence, this research launches a new pathway for the progress of cheap and earth-abundant electrocatalyst for future applications.