# Homogeneous Spatial Distribution of Deuterium Chemisorbed on Free-Standing Graphene

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## Abstract

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## 1. Introduction

## 2. Materials and Methods

## 3. Results and Discussion

## 4. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## Abbreviations

XPS | X ray Photoelectron Spectroscopy |

NPG | Nano Porous Graphene |

UHV | Ultra High Vacuum |

3D | Three Dimensional |

2D | Two Dimensional |

## References

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**Figure 1.**(

**a**) Raman spectra taken on the pristine (red line) and deuterated NPG (blue line) sample, acquired with a $\lambda $ = 532.2 nm excitation laser; in the inset we see the zoomed region of G and D′ bands with Lorentzian fitting. (

**b**,

**c**) Deuterated-NPG: spatial mappings of the I${}_{\mathrm{D}}$/I${}_{\mathrm{G}}$ and I${}_{\mathrm{D}\prime}$/I${}_{\mathrm{G}}$ intensity ratios, respectively, over an area of 10 $\mathsf{\mu}$m × 10 $\mathsf{\mu}$m with a 500-nm step. (

**d**,

**e**) Deuterated-NPG: occurrence distribution of the I${}_{\mathrm{D}}$/I${}_{\mathrm{G}}$ and I${}_{\mathrm{D}\prime}$/I${}_{\mathrm{G}}$ intensity ratios, respectively ($\mu $, mean value; $\sigma $, standard deviation).

**Figure 2.**C 1s core level XPS spectra and fitting curves for clean pristine NPG (

**a**) and deuterated-NPG (

**b**); experimental data (black dots), sp${}^{2}$ fitting component (blue areas), sp${}^{3}$ component (green areas), CO${}_{x}$ component (yellow areas), Shirley background (violet lines), and fitting sum curve (red lines). An SEM image of NPG is reported in the inset to panel (

**a**).

**Figure 3.**(

**a**) Carbon KVV N(E) Auger electron spectroscopy peak taken on two different spatial points of the deuterated NPG (blue and red lines). (

**b**) Numerically derived first derivative [dN(E)/dE] of the C KVV Auger signal from panel (

**a**) compared with the derivative of the Auger signal for the pristine NPG (black lines). (

**c**) C 1s core-level XPS spectra in a zoomed binding energy region and fitting curves, taken in the same spatial points of the deuterated NPG; experimental data (black dots), sp${}^{2}$ fitting component (blue areas), sp${}^{3}$ component (green areas), CO${}_{x}$ component (yellow areas), Shirley background (black lines), and fitting sum curve (red lines).

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## Share and Cite

**MDPI and ACS Style**

Betti, M.G.; Blundo, E.; De Luca, M.; Felici, M.; Frisenda, R.; Ito, Y.; Jeong, S.; Marchiani, D.; Mariani, C.; Polimeni, A.; Sbroscia, M.; Trequattrini, F.; Trotta, R. Homogeneous Spatial Distribution of Deuterium Chemisorbed on Free-Standing Graphene. *Nanomaterials* **2022**, *12*, 2613.
https://doi.org/10.3390/nano12152613

**AMA Style**

Betti MG, Blundo E, De Luca M, Felici M, Frisenda R, Ito Y, Jeong S, Marchiani D, Mariani C, Polimeni A, Sbroscia M, Trequattrini F, Trotta R. Homogeneous Spatial Distribution of Deuterium Chemisorbed on Free-Standing Graphene. *Nanomaterials*. 2022; 12(15):2613.
https://doi.org/10.3390/nano12152613

**Chicago/Turabian Style**

Betti, Maria Grazia, Elena Blundo, Marta De Luca, Marco Felici, Riccardo Frisenda, Yoshikazu Ito, Samuel Jeong, Dario Marchiani, Carlo Mariani, Antonio Polimeni, Marco Sbroscia, Francesco Trequattrini, and Rinaldo Trotta. 2022. "Homogeneous Spatial Distribution of Deuterium Chemisorbed on Free-Standing Graphene" *Nanomaterials* 12, no. 15: 2613.
https://doi.org/10.3390/nano12152613