Abstract: The preparation cost of high-purity hydrogen is high, and the development and utilization of low-cost industrial by-product hydrogen as an alternative gas source is considered an effective way to significantly reduce hydrogen storage costs. Industrial by-product hydrogen typically contains components such as H2S and CO, but the poisoning mechanisms of these gases on the superlattice hydrogen storage alloy during hydrogen absorption and desorption are not well understood. This study systematically investigates the poisoning effects and regeneration behavior of La0.65Mg1.32Ca1.03Ni9Y0.17 superlattice hydrogen storage alloy in 10-3 H2S and CO atmospheres. The experiment adopts a 10 poisoning cycles+1 regeneration mode, with a total of 20 poisoning cycles and 2 pure hydrogen regenerations. The results show that the hydrogen storage capacity of this alloy gradually decreases after 22 cycles in pure hydrogen, but it can be effectively restored after dehydrogenation at 473 K. In the presence of impurity gases, the hydrogen storage capacity retention rates after 10 poisoning cycles with H2S and CO are 3.56% and 2.71%, respectively; after 20 cycles, these values decrease to 3.68% and 1.73%, respectively. After dehydrogenation at 473 K, the retention rates are restored to 40.35% and 98.27%. This indicates that the severity of poisoning by impurity gases follows the order: CO>H2S, while the difficulty of regeneration follows the order: H2S>CO. X-ray diffraction analysis shows that after poisoning, the main phase of the alloy changes from AB3 to AB3H, but it recovers after high-temperature dehydrogenation. X-ray photoelectron spectroscopy results show that after poisoning by H2S, CaS and CaSO4 are formed on the surface of the hydrogen storage alloy, indicating irreversible chemical adsorption. In contrast, after poisoning by CO, no new substances are formed on the alloy surface, indicating that the poisoning effect is due to reversible adsorption. This study clarifies the differentiated poisoning mechanisms of various impurity gases and provides theoretical support for the application of rare-earth superlattice hydrogen storage alloys in complex atmospheres.

Key words: superlattice hydrogen storage alloys, anti-poisoning performance, poisoning mechanism, regeneration performance

摘要： 本工作系统考察了体积分数为10-3的H2S和CO杂质气源对La0.65Mg1.32Ca1.03Ni9Y0.17合金储氢性能的毒化效应及再生行为。毒化过程以10次为一组经再生后再次循环(共20次毒化，2次纯氢再生)。结果表明，对比实验储氢合金，在22次纯氢循环中表现出一定容量衰减，但经473 K高温脱氢可有效恢复。在杂质气体环境中，该储氢合金经H2S和CO毒化10次后的容量保留率分别为3.56%和2.71%，473 K脱氢后均大幅回升；毒化20次后的容量保留率分别为3.68%和1.73%，经473 K高温脱氢后分别回升至40.35%和98.27%。表明杂质气体对储氢合金的毒化强度为CO>H2S，再生难度为H2S>CO。X射线衍射结果显示，储氢合金被毒化后转变为AB3H相，高温脱氢可恢复AB3主相。X射线光电子能谱分析揭示H2S毒化后储氢合金表面生成CaS和CaSO4，表明其为不可逆化学吸附；而CO毒化未产生新物质，显示其毒化作用主要为可逆吸附。该工作不仅阐明了杂质气体的差异化毒化机理，也为稀土超晶格储氢合金在复杂气氛下的储氢应用提供了理论支撑。

关键词: 超晶格储氢合金, 抗毒化性能, 毒化机制, 再生性能