Rare-earth AB-type alloys have great application potential in solid-state hydrogen storage. To further improve their plateau characteristics and cycling life, the effects of Fe on the long-term hydrogen storage properties of LaNiFe ( = 0, 0.5, 1) alloys are studied, and the function mechanisms are revealed. Fe induces a (Fe,Ni) phase layer with good ductility around LaNi main phase, which plays a buffer role to relieve the microstrain during hydrogen absorption/desorption, thus stabilizing the crystal structure and improving the cycling performance. Further, Fe with larger atomic radius than Ni relieves the compression from 12 to 6 site of the LaNi phase, and suppresses the plateau splitting phenomenon, resulting in a single and long hydrogen absorption/desorption plateau throughout 1000 cycles. This study promotes the understanding and application of cheap and effective Fe in improving the hydrogen storage properties of AB-type alloys during long-term cycling.

中文翻译：

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Fe改善AB5型储氢合金循环稳定性和平台特性的作用机制

稀土AB型合金在固态储氢方面具有巨大的应用潜力。为了进一步改善LaNiFe(=0,0.5,1)合金的平台特性和循环寿命，研究了Fe对LaNiFe(=0,0.5,1)合金长期储氢性能的影响，并揭示了其作用机制。 Fe在LaNi主相周围诱导形成具有良好延展性的(Fe,Ni)相层，起到缓冲作用，缓解吸放氢过程中的微应变，从而稳定晶体结构，提高循环性能。此外，原子半径比Ni大的Fe缓解了LaNi相12位至6位的压缩，并抑制平台分裂现象，导致在1000个循环中出现单一且长的氢吸收/脱附平台。这项研究促进了人们对廉价有效的Fe在改善AB型合金长期循环过程中储氢性能方面的理解和应用。