ABSTRACT TiFe‐based hydrogen storage alloys have garnered significant attention because of their cost‐effectiveness, high hydrogen capacity, and favorable hydrogen absorption/desorption characteristics. However, practical application was limited by activation challenges and sensitivity to environmental poisoning. This study explores a highly effective engineering strategy to overcome these limitations by incorporating excess Ti with tunable Ce doping in TiFe‐based alloys. Such engineered Ti 1‐ x Ce x Fe 0.75 Mn 0.06 Co 0.06 ( x = 0, 0.02, 0.04, 0.06) alloys, by virtue of doping Ce for excess Ti, can significantly improve activation at room temperature while maintaining high hydrogen storage capacity. Notably, the alloy with x = 0.04 achieves a peak hydrogen storage capacity of 1.94 wt% and an effective capacity of 1.85 wt%, highlighting the remarkably enhanced storage potential. We additionally verify Ce doping can effectively improve its cyclic durability for hydrogen storage, reducing capacity attenuation from 14.21% to 2.06%. The residual hydrogen storage capacity—a key factor for efficient desorption—decreased from 0.172 wt% to as low as 0.036 wt%, indicating enhanced desorption efficiency. Furthermore, this study reveals a gradual shift in the activation mechanism—from an initial reliance on excess Ti to a Ce‐driven process—marking a transformative step in alloy design for reliable hydrogen storage applications.
Li et al. (Sun,) studied this question.