Abstract：
Nanostructured metal hydrides with unique morphology and improved hydrogen storage properties have attracted intense interests. However, the study of the growth process of highly active borohydrides remains challenging. Herein, for the first time the synthesis of LiBH4 nanorods through a hydrogen-assisted one-pot solvothermal reaction is reported. Reaction of n-butyl lithium with triethylamine borane in n-hexane under 50 bar of H2 at 40-100 °C gives rise to the formation of the [100]-oriented LiBH4 nanorods with 500-800 nm in diameter, whose growth is driven by orientated attachment and ligand adsorption. The unique morphology enables the LiBH4 nanorods to release hydrogen from ≈184 °C, 94 °C lower than the commercial sample (≈278 °C). Hydrogen release amounts to 13 wt% within 40 min at 450 °C with a stable cyclability, remarkably superior to the commercial LiBH4 (≈9.1 wt%). More importantly, up to 180 °C reduction in the onset temperature of hydrogenation is successfully attained by the nanorod sample with respect to the commercial counterpart. The LiBH4 nanorods show no foaming during dehydrogenation, which improves the hydrogen cycling performance. The new approach will shed light on the preparation of nanostructured metal borohydrides as advanced functional materials.
摘要：
具有独特形态和改进的储氢性能的纳米结构金属氢化物引起了人们的强烈兴趣。然而,研究高活性硼氢化物的生长过程仍然具有挑战性。在这里，首次报道了通过氢辅助一锅溶剂热反应合成LiBH4纳米棒。正丁基锂与三乙胺硼烷在正己烷中在50巴的H2下在40-100°C下反应，形成了直径为500-800nm的[100]取向的LiBH4纳米棒，其生长是由定向附着和配体吸附驱动的。独特的形态使LiBH4纳米棒能够从≈184°C释放氢，比商业样品低94°C(≈278°C)。在450°C下40分钟内氢释放量为13wt％，具有稳定的循环能力，显著优于商业LiBH4(≈9.1重量%)。更重要的是,相对于商业对应物,通过纳米棒样品成功地实现了氢化起始温度的高达180°C的降低。LiBH4纳米棒在脱氢过程中没有起泡，提高了氢气循环性能。新方法将揭示纳米结构金属硼氢化物作为高级功能材料的制备。
