H₂ Storage Projects

Transition Metal-Decorated Nanotubes and C ₆₀; high-capacity hydrogen storage medium

Introduction | Dissociative Absorption of H2 | Molecular Absorption | 4th top-H2 | The lowest energy isomer | Bonding Mechanism | Does Pt/Pd also work? | MD simulations | High concentration metal-coverages | Ti-decorated C60 | Conclusions

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Molecular Adsorption of the fourth top H₂ over Ti-SWNT

Fig. 1c shows the energy evolution when a fourth hydrogen molecule approaches the t80TiH 2- 2H 2 system from the top. The energy again decreases continuously, indicating a zero-energy barrier. The final product, denoted as t80TiH 2- 3H 2, is shown in the inset with the relevant structural parameters. The energy gained by the fourth adsorption, 0.34 eV/H 2, is slightly smaller than for the other cases but is still substantial. The H-H distance of the top H 2 is 0.86 Å. Several attempts to add a fifth hydrogen molecule at a variety of positions failed, suggesting a limit of 4 H 2/Ti.

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