Hydrogen storage on nitrogen induced defects in palladium-decorated graphene: A first-principles study
Hydrogen storage on nitrogen induced defects in palladium-decorated graphene: A first-principles study
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DOI：
10.1016/j.apsusc.2013.12.080
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发表时间：
2014-02
影响因子：
6.7
通讯作者：
Ling Ma;Ling Ma;Jian-min Zhang;K. Xu
中科院分区：
文献类型：
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作者：
Ling Ma;Ling Ma;Jian-min Zhang;K. Xu
利用基于密度泛函理论（DFT）计算的第一原理研究了pd修饰的氮掺杂石墨烯的结构和储氢行为。在这三种缺陷结构中，发现掺杂吡啶和吡啶氮的Pd修饰石墨烯更稳定，并表现出高达3个H2per Pd原子的吸氢能力。单个h2o2或两个h2o2分子化学吸附在Pd原子上，其中拉伸的h单键h键被松弛但未解离。H2分子的结合机制是Pd分子的4d轨道与H2分子的σ轨道的杂化（Kubas相互作用）。在两个被吸附的H2中，第一个和第二个H2仍然是分子化学吸附的，第三个被吸附的H2的成键性质是非常弱的物理吸附。具有吡啶和吡啶N缺陷的双面pd修饰石墨烯理论上可以达到1.99 wt.%氢的重量容量，这与最近的实验发现非常接近。
The structure and hydrogen storage behavior of Pd-decorated nitrogen-doped graphene are investigated using the first principals based on density functional theory (DFT) calculations. Among the three types of defective structures, it is found that Pd-decorated graphene with pyridinic and pyrrolic N-doped defects are more stable and exhibit hydrogen uptake ability up to three H2per Pd atom. A single H2or two H2are molecularly chemisorbed on the Pd atom, where the stretched Hsingle bondH bond is relaxed but not dissociated. The binding mechanism of H2molecule is attributed to hybridization of the 4d orbitals of Pd with the σ orbitals of H2(so-called Kubas interaction). Out of two adsorbed H2, the first and second H2are still chemisorbed molecularly, the nature of bonding is very weak physisorption for the third adsorbed H2. Double-side Pd-decorated graphene with pyridinic and pyrrolic N defects can theoretically reach a gravimetric capacity of 1.99 wt.% hydrogen, which is very close to the recent experimental finding.