Dual-Functional Al-Doped Co x S v Nanoneedle Arrays: Enhanced Supercapacitive Energy Storage and Electrocatalytic Water Splitting

Against the backdrop of escalating global energy demands and the gradual depletion of conventional fossil fuels, water electrolysis has emerged as a pivotal pathway for achieving clean and sustainable hydrogen utilization. In this study, Co x S v nanomaterials were successfully synthesized via a facile hydrothermal method. Strategic incorporation of aluminum ions induced structural modifications, effectively augmenting both specific surface area and active site density, thereby substantially enhancing the electrochemical performance of the electrode materials. Experimental results demonstrate that the Al-doped Co x S v electrode with 0.45 mmol Al addition achieves an exceptional areal capacitance of 418.2 C·cm –2, showcasing superior supercapacitive behavior. Notably, the optimized Al–Co x S v electrode with 0.15 mmol Al doping exhibits a significantly reduced hydrogen evolution overpotential of 228.3 mV at 10 mA·cm –2, highlighting remarkable electrocatalytic enhancement.