Abstract The addition of transition metals to alkali intercalated fullerides proved to enhance their already good hydrogen absorption properties. Herein we present a study based on two different synthetic strategies, allowing the addition of nickel as aggregates with different size to the lithium fulleride Li6C60: the former is based on the metathesis of nickel chloride, while the latter on the thermal decomposition of nickel carbonyl clusters. The hydrogen-storage properties of the obtained materials have been investigated with manometric and calorimetric measurements, which indicated a clear enhancement of the final absorption value and kinetics with respect to pristine Li6C60, as a consequence of nickel surface catalytic activity towards hydrogen molecules dissociation. We found up to 10 % increase of the total H2 weight % absorbed (5.5 wt% H2) in presence of Ni aggregates. Furthermore, the control of the transition metal particles size distribution allowed reducing the hydrogen desorption enthalpy of the systems.

中文翻译：

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添加镍以优化锂插层富勒烯的储氢性能

摘要 向碱金属插层富勒化物中添加过渡金属被证明可以增强它们本已良好的吸氢性能。在此，我们提出了一项基于两种不同合成策略的研究，允许将镍作为不同尺寸的聚集体添加到富勒酸锂 Li6C60 中：前者基于氯化镍的复分解，而后者基于羰基镍簇的热分解. 所得材料的储氢性能已通过测压和量热测量进行研究，这表明由于镍表面对氢分子解离的催化活性，原始 Li6C60 的最终吸收值和动力学明显增强。我们发现吸收的总 H2 重量百分比增加了 10% (5. 5 wt% H2) 在 Ni 聚集体的存在下。此外，过渡金属粒度分布的控制允许降低系统的氢解吸焓。