Enhanced dehydrogenation properties of LiAlH4-Mg2NiH4 nanocomposites via doping Ti-based catalysts
Enhanced dehydrogenation properties of LiAlH4-Mg2NiH4 nanocomposites via doping Ti-based catalysts
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通过掺杂钛基催化剂增强LiAlH4-Mg2NiH4纳米复合材料的脱氢性能
DOI：
10.1088/2053-1591/ab196f
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发表时间：
2019
影响因子：
2.3
通讯作者：
Li Liquan
中科院分区：
文献类型：
--
作者：
Ma Zhongliang;Liu Jiangchuan;Zhao Yingyan;Zhang Jiguang;Zhu Yunfeng;Zhang Yao;Liu Yana;Li Liquan
金属铝镁基氢化物配合物具有推广储氢材料在储能系统中应用的潜力。研究了含Ti基添加剂的LiAlH 4-Mg 2NiH 4失稳体系的储氢性能。TiF 3的掺杂显著提高了LiAlH 4-Mg 2NiH 4的放氢温度和放氢动力学，超过了Ti和TiO 2掺杂的LiAlH 4-Mg 2NiH 4复合材料。特别是TiF 3掺杂的LiAlH 4-Mg 2NiH 4复合材料的起始脱氢温度降低到50 ℃，远上级未掺杂的样品以及Ti和TiO 2掺杂的样品。用Johnson-Mehl-Avrami模型拟合出TiF 3掺杂的LiAlH 4-Mg 2NiH 4复合材料的放氢活化能为81.56kJ mol− 1，低于未掺杂的LiAlH 4-Mg 2NiH 4复合材料的放氢活化能（85.30kJ mol− 1）。XPS结果表明，在放氢过程中原位生成Al 3 Ti（Ti 0）相，对TiF 3掺杂的LiAlH 4-Mg 2NiH 4复合材料的放氢具有积极的催化作用。此外，TiF 3掺杂的LiAlH 4-Mg 2NiH 4复合材料也表现出良好的再氢化性能.
Metal alanate and magnesium-based hydride complex has potential to promote the application of hydrogen storage materials in energy storage systems. In this work, the hydrogen storage properties of LiAlH 4–Mg 2 NiH 4 destabilized system with Ti-based additives were investigated. Both the dehydrogenation temperature and kinetics of LiAlH 4–Mg 2 NiH 4 were significantly improved by doping TiF 3, surpassing those of the Ti-and TiO 2-doped LiAlH 4–Mg 2 NiH 4 composites. Particularly, the onset dehydrogenation temperature of the TiF 3 doped LiAlH 4–Mg 2 NiH 4 composite was reduced to as low as 50 C, far superior to that of the undoped sample and the Ti-and TiO 2-doped samples. The hydrogen desorption activation energy of TiF 3-doped LiAlH 4–Mg 2 NiH 4 composite was 81.56 kJ mol− 1 fitted by Johnson–Mehl–Avrami model, which was lower than that of the undoped composite (85.30 kJ mol− 1). The XPS results indicated that Al 3 Ti (Ti 0) phase could be in situ formed during dehydrogenation process, exerting positive catalytic effect on the dehydrogenation of the TiF 3-doped LiAlH 4–Mg 2 NiH 4 composite. Moreover, the TiF 3-doped LiAlH 4–Mg 2 NiH 4 composite also exhibited desirable re-hydrogenation behavior.