<p>Despite the development of Mg-based hydrogen storage alloys over decades, undesired particle growth and poorly controlled interfacial connectivity have remained unsolved, significantly degrading their hydrogen storage capability. These challenges majorly arise from the uniformly dispersed multiple phases of alloys. Here, we report that the NdH<sub>2</sub> exposed Mg-Mg<sub>2</sub>Ni nanocomposite (NdH<sub>2</sub>@Mg-Mg<sub>2</sub>Ni), realized via a scalable hot-extrusion and hydrogen-induced in-situ decomposition, can address the above-mentioned issues. In it, Mg serves as hydrogen storage phase while NdH<sub>2</sub> and Mg<sub>2</sub>Ni serve as catalytically active sites for hydrogen dissociation, diffusion, and nucleation, respectively. In addition, the surface exposed NdH<sub>2</sub> nanoparticles serve as the pinning center, not only ensuring the Mg-Mg<sub>2</sub>Ni interfacial connection but also avoiding the direct contact of each particle. Consequently, NdH<sub>2</sub>@Mg-Mg<sub>2</sub>Ni enables one of the lowest hydrogen release temperatures (176.2 °C) among the Mg-based alloys, releasing 5.1 wt.% H<sub>2</sub> even at 180 °C. Thanks to the selective NdH<sub>2</sub> exposure, NdH<sub>2</sub>@Mg-Mg<sub>2</sub>Ni exhibits an exceptional chemical and morphological stability, enabling robust hydrogen storage capability over 3700 cycles. The present study proposes a facile and scalable approach to optimize multiple-phase morphology and chemical properties of Mg-based hydrogen storage materials.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Selective NdH2 exposure enhances hydrogen storage capability of Mg-Mg2Ni nanocomposites over 3700 cycles

  • Xuan Sun,
  • Longbing Gu,
  • Yangfan Lu,
  • Qun Luo,
  • Bin Hu,
  • Jianbo Li,
  • Chengzhang Wu,
  • Yu Zhang,
  • Qinfen Gu,
  • Qian Li

摘要

Despite the development of Mg-based hydrogen storage alloys over decades, undesired particle growth and poorly controlled interfacial connectivity have remained unsolved, significantly degrading their hydrogen storage capability. These challenges majorly arise from the uniformly dispersed multiple phases of alloys. Here, we report that the NdH2 exposed Mg-Mg2Ni nanocomposite (NdH2@Mg-Mg2Ni), realized via a scalable hot-extrusion and hydrogen-induced in-situ decomposition, can address the above-mentioned issues. In it, Mg serves as hydrogen storage phase while NdH2 and Mg2Ni serve as catalytically active sites for hydrogen dissociation, diffusion, and nucleation, respectively. In addition, the surface exposed NdH2 nanoparticles serve as the pinning center, not only ensuring the Mg-Mg2Ni interfacial connection but also avoiding the direct contact of each particle. Consequently, NdH2@Mg-Mg2Ni enables one of the lowest hydrogen release temperatures (176.2 °C) among the Mg-based alloys, releasing 5.1 wt.% H2 even at 180 °C. Thanks to the selective NdH2 exposure, NdH2@Mg-Mg2Ni exhibits an exceptional chemical and morphological stability, enabling robust hydrogen storage capability over 3700 cycles. The present study proposes a facile and scalable approach to optimize multiple-phase morphology and chemical properties of Mg-based hydrogen storage materials.