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Detection of hydrogen using graphene.

Ehemann RC, Krstić PS, Dadras J, Kent PR, Jakowski J - Nanoscale Res Lett (2012)

Bottom Line: Irradiation dynamics of a single graphene sheet bombarded by hydrogen atoms is studied in the incident energy range of 0.1 to 200 eV.Results for reflection, transmission, and adsorption probabilities, as well as effects of a single adsorbed atom to the electronic properties of graphene, are obtained by the quantum-classical Monte Carlo molecular dynamics within a self-consistent-charge-density functional tight binding formalism We compare these results with those, distinctly different, obtained by the classical molecular dynamics.PACS: 61.80.Az, 61.48.Gh, 61.80.Jh, 34.50.Dy.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Physics and Astronomy, Middle Tennessee State University, Murfreesboro, TN, 37130, USA. rce2g@mtmail.mtsu.edu.

ABSTRACT
Irradiation dynamics of a single graphene sheet bombarded by hydrogen atoms is studied in the incident energy range of 0.1 to 200 eV. Results for reflection, transmission, and adsorption probabilities, as well as effects of a single adsorbed atom to the electronic properties of graphene, are obtained by the quantum-classical Monte Carlo molecular dynamics within a self-consistent-charge-density functional tight binding formalism We compare these results with those, distinctly different, obtained by the classical molecular dynamics.PACS: 61.80.Az, 61.48.Gh, 61.80.Jh, 34.50.Dy.

No MeSH data available.


Related in: MedlinePlus

Probabilities of reflection, transmission, and adsorption as calculated by AIREBO and REBO [5,30]. The presence of potential barriers before potential wells (see Figure 10) results primarily in reflection at low incident energies.
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Figure 11: Probabilities of reflection, transmission, and adsorption as calculated by AIREBO and REBO [5,30]. The presence of potential barriers before potential wells (see Figure 10) results primarily in reflection at low incident energies.

Mentions: Ito et al. [6,30], Nakamura et al. [5], and Saito et al. [33] have done a comprehensive study of the response of a single graphene sheet (reflection, transmission, and absorption) to the impact of hydrogen atoms and its isotopes in an energy range below 200 eV. They used classical molecular dynamics simulations with the short-range (< 2 Å) modified Brenner (REBO) potential. Unfortunately, the distribution of barriers and wells is not clear for their modification of the potential; however, their calculation of the reflection, transmission, and adsorption probabilities upon normal impact shows good qualitative agreement with our AIREBO calculations, as illustrated in Figure 11. Classical MD AIREBO and REBO results are significantly different than the quantum-classical SCC-DFTB results mainly due to the presence of the potential barriers observed in Figure 10. The AIREBO and REBO graphene potentials are more repulsive than those of SCC-DFTB, which results in a 15 eV higher threshold for transmission to occur. However, all methods converge to 100% transmission at high energies, as has been observed in previous studies [8]. While REBO shows a much higher peak in adsorption probability, the presence of the aforementioned barriers in both potentials result in a dominance of reflection at low energies, inconsistent with the results of SCC-DFTB presented above.


Detection of hydrogen using graphene.

Ehemann RC, Krstić PS, Dadras J, Kent PR, Jakowski J - Nanoscale Res Lett (2012)

Probabilities of reflection, transmission, and adsorption as calculated by AIREBO and REBO [5,30]. The presence of potential barriers before potential wells (see Figure 10) results primarily in reflection at low incident energies.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3369821&req=5

Figure 11: Probabilities of reflection, transmission, and adsorption as calculated by AIREBO and REBO [5,30]. The presence of potential barriers before potential wells (see Figure 10) results primarily in reflection at low incident energies.
Mentions: Ito et al. [6,30], Nakamura et al. [5], and Saito et al. [33] have done a comprehensive study of the response of a single graphene sheet (reflection, transmission, and absorption) to the impact of hydrogen atoms and its isotopes in an energy range below 200 eV. They used classical molecular dynamics simulations with the short-range (< 2 Å) modified Brenner (REBO) potential. Unfortunately, the distribution of barriers and wells is not clear for their modification of the potential; however, their calculation of the reflection, transmission, and adsorption probabilities upon normal impact shows good qualitative agreement with our AIREBO calculations, as illustrated in Figure 11. Classical MD AIREBO and REBO results are significantly different than the quantum-classical SCC-DFTB results mainly due to the presence of the potential barriers observed in Figure 10. The AIREBO and REBO graphene potentials are more repulsive than those of SCC-DFTB, which results in a 15 eV higher threshold for transmission to occur. However, all methods converge to 100% transmission at high energies, as has been observed in previous studies [8]. While REBO shows a much higher peak in adsorption probability, the presence of the aforementioned barriers in both potentials result in a dominance of reflection at low energies, inconsistent with the results of SCC-DFTB presented above.

Bottom Line: Irradiation dynamics of a single graphene sheet bombarded by hydrogen atoms is studied in the incident energy range of 0.1 to 200 eV.Results for reflection, transmission, and adsorption probabilities, as well as effects of a single adsorbed atom to the electronic properties of graphene, are obtained by the quantum-classical Monte Carlo molecular dynamics within a self-consistent-charge-density functional tight binding formalism We compare these results with those, distinctly different, obtained by the classical molecular dynamics.PACS: 61.80.Az, 61.48.Gh, 61.80.Jh, 34.50.Dy.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Physics and Astronomy, Middle Tennessee State University, Murfreesboro, TN, 37130, USA. rce2g@mtmail.mtsu.edu.

ABSTRACT
Irradiation dynamics of a single graphene sheet bombarded by hydrogen atoms is studied in the incident energy range of 0.1 to 200 eV. Results for reflection, transmission, and adsorption probabilities, as well as effects of a single adsorbed atom to the electronic properties of graphene, are obtained by the quantum-classical Monte Carlo molecular dynamics within a self-consistent-charge-density functional tight binding formalism We compare these results with those, distinctly different, obtained by the classical molecular dynamics.PACS: 61.80.Az, 61.48.Gh, 61.80.Jh, 34.50.Dy.

No MeSH data available.


Related in: MedlinePlus