论文标题
增强的氢碳纳米管中的氢存储：第一原理研究
Enhanced Hydrogen Storage in Gold-doped Carbon Nanotubes: A first-principles study
论文作者
论文摘要
吸附的材料是推进氢存储技术的有前途的替代方法。一般的缺点是相对较弱的固体气体相互作用和吸附能，可提供低重量和体积能力以及极端的操作条件。在这里，我们提出了掺杂的碳纳米管（CNT）作为在高温下可逆氢捕获的有效替代方案。这项工作使用密度功能理论研究了几种修饰CNT的性质。我们分析了均匀的AU掺杂CNT的结合和形成能，并评估其吸附能力。使用状态的部分密度对纳米结构的氢存储机制进行了深入研究，并进行了电荷转移分析，表明直径的增加对结果具有积极影响。我们的发现表明，修饰的结构能够捕获每个金原子的六到九个氢分子，达到154至330 g/l的体积能力超过了DOE靶标。此外，计算出的解吸温度表明Au掺杂的CNT的高性能，获得了200 k以上的氢捕获释放释放工作条件。
Sorbent materials are a promising alternative to advance hydrogen storage technologies. The general disadvantage is the relatively weak solid-gas interaction and adsorption energy, providing low gravimetric and volumetric capacities and extreme operational conditions. Here we propose Au-doped carbon nanotubes (CNTs) as an efficient alternative for reversible hydrogen capture at high temperatures. This work investigates the properties of several modified CNTs using density functional theory. We analyze the binding and formation energies of the uniformed Au-doped CNTs and assess their adsorption capability. The hydrogen storage mechanisms of the nanostructures are studied in depth using partial density of states and charge transfer analysis showing that the increase of diameter has a positive effect on the outcome. Our findings show that the modified structures are able to capture from six to nine hydrogen molecules per gold atom, achieving volumetric capacities ranging from 154 to 330 g/l, surpassing the DOE target. In addition, the calculated desorption temperatures indicate high performance of Au-doped CNTs, obtaining hydrogen capture-release working conditions above 200 K.
