High-performance hydrogen generation via activated Al–Bi2Se3 composite materials†

Abstract

Al-based composites have emerged as promising hydrogen generation materials due to their high yield and low cost, yet slow hydrogen generation kinetics have impeded their widespread application. In this study, a series of novel Al–Bi_xM_y composites were synthesized via high-energy ball milling, with the Al–15 wt% Bi₂Se₃ composite demonstrating superior hydrogen generation performance. Achieving an unprecedented catalytic efficiency at ambient conditions, this composite reached a maximum hydrogen generation (MHG) rate of 1139 mL g⁻¹ min⁻¹ and completed hydrogen generation within 5 min with a 97.6% conversion yield. Through comprehensive characterization using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS), in situ Se and Bi were found on the fresh Al surface. Density functional theory calculations (DFT) elucidated the mechanism by which Bi doping enhances water adsorption and the cleavage of O–H bonds. These findings provide important insights for the design of high-performance Al-based hydrogen generation materials with improved kinetics and efficiency.