Condensed Matter Theory Group, Department of Physics and Astronomy, Box 516, Uppsala University, S-75120 Uppsala (Sweden).
Chemphyschem. 2013 Oct 21;14(15):3463-6. doi: 10.1002/cphc.201300548. Epub 2013 Sep 5.
First-principles calculations based on density functional theory are used to investigate the electronic structure along with the stability, bonding mechanism, band gap, and charge transfer of metal-functionalized silicene to envisage its hydrogen-storage capacity. Various metal atoms including Li, Na, K, Be, Mg, and Ca are doped into the most stable configuration of silicene. The corresponding binding energies and charge-transfer mechanisms are discussed from the perspective of hydrogen-storage compatibility. The Li and Na metal dopants are found to be ideally suitable, not only for strong metal-to-substrate binding and uniform distribution over the substrate, but also for the high-capacity storage of hydrogen. The stabilities of both Li- and Na-functionalized silicene are also confirmed through molecular dynamics simulations. It is found that both of the alkali metals, Li(+) and Na(+), can adsorb five hydrogen molecules, attaining reasonably high storage capacities of 7.75 and 6.9 wt %, respectively, with average adsorption energies within the range suitable for practical hydrogen-storage applications.
基于密度泛函理论的第一性原理计算被用于研究金属功能化硅烯的电子结构以及稳定性、成键机制、带隙和电荷转移，以预测其储氢能力。包括 Li、Na、K、Be、Mg 和 Ca 在内的各种金属原子被掺杂到硅烯的最稳定构型中。从储氢相容性的角度讨论了相应的结合能和电荷转移机制。研究发现，Li 和 Na 金属掺杂剂不仅非常适合于强金属-基底结合和基底上的均匀分布，而且还非常适合于高容量储氢。通过分子动力学模拟也证实了 Li 和 Na 功能化硅烯的稳定性。研究发现，这两种碱金属 Li(+)和 Na(+)都可以吸附五个氢分子，分别达到 7.75%和 6.9%的合理高储氢容量，平均吸附能在适合实际储氢应用的范围内。
