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Purification/annealing of graphene with 100-MeV Ag ion irradiation.

Kumar S, Tripathi A, Singh F, Khan SA, Baranwal V, Avasthi DK - Nanoscale Res Lett (2014)

Bottom Line: We report swift heavy ion (SHI) irradiation-induced annealing and purification effects in graphene films, similar to that observed in our studies on fullerenes and carbon nanotubes (CNTs).This indicates that SHI induces annealing effects at lower fluences.The results suggest that SHI irradiation fluence may be used as one of the tools for defect annealing and manipulation of the number of graphene layers. 60.80.x; 81.05.ue.

View Article: PubMed Central - HTML - PubMed

Affiliation: Materials Science Group, Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067, India.

ABSTRACT

Unlabelled: Studies on interaction of graphene with radiation are important because of nanolithographic processes in graphene-based electronic devices and for space applications. Since the electronic properties of graphene are highly sensitive to the defects and number of layers in graphene sample, it is desirable to develop tools to engineer these two parameters. We report swift heavy ion (SHI) irradiation-induced annealing and purification effects in graphene films, similar to that observed in our studies on fullerenes and carbon nanotubes (CNTs). Raman studies after irradiation with 100-MeV Ag ions (fluences from 3 × 10(10) to 1 × 10(14) ions/cm(2)) show that the disorder parameter α, defined by I D/I G ratio, decreases at lower fluences but increases at higher fluences beyond 1 × 10(12) ions/cm(2). This indicates that SHI induces annealing effects at lower fluences. We also observe that the number of graphene layers is reduced at fluences higher than 1 × 10(13) ions/cm(2). Using inelastic thermal spike model calculations, we estimate a radius of 2.6 nm for ion track core surrounded by a halo extending up to 11.6 nm. The transient temperature above the melting point in the track core results in damage, whereas lower temperature in the track halo is responsible for annealing. The results suggest that SHI irradiation fluence may be used as one of the tools for defect annealing and manipulation of the number of graphene layers.

Pacs: 60.80.x; 81.05.ue.

No MeSH data available.


Related in: MedlinePlus

Atomic force microscopy imaging and corresponding section analyses of irradiated part of samples. Atomic force microscopy imaging of irradiated part of graphene is shown at fluences (a) 1 × 1013, (c) 3 × 1013 and (e) 1 × 1014 ions/cm2, and corresponding section analyses is shown in (b), (d) and (f), respectively.
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Figure 10: Atomic force microscopy imaging and corresponding section analyses of irradiated part of samples. Atomic force microscopy imaging of irradiated part of graphene is shown at fluences (a) 1 × 1013, (c) 3 × 1013 and (e) 1 × 1014 ions/cm2, and corresponding section analyses is shown in (b), (d) and (f), respectively.

Mentions: Atomic force microscopy imaging (Figure 10) also confirms the reduction in number of layers at different places of irradiated samples and shows that at higher fluence (above 1 × 1013 ions/cm2) there is more coverage of one- and two-layer graphene instead of three to four layers observed before irradiation. The ion irradiation-induced ablation in graphene can be used for controlling the number of layers with spatial selectivity. Similar reduction in the number of graphene layers with laser ablation above a given threshold laser energy density has been demonstrated by Dhar et al. [54]. This shows the possibility of manipulating regions with varying number of graphene layers. This spatial selectivity of layers is desirable for engineering the properties for the device applications.


Purification/annealing of graphene with 100-MeV Ag ion irradiation.

Kumar S, Tripathi A, Singh F, Khan SA, Baranwal V, Avasthi DK - Nanoscale Res Lett (2014)

Atomic force microscopy imaging and corresponding section analyses of irradiated part of samples. Atomic force microscopy imaging of irradiated part of graphene is shown at fluences (a) 1 × 1013, (c) 3 × 1013 and (e) 1 × 1014 ions/cm2, and corresponding section analyses is shown in (b), (d) and (f), respectively.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4012553&req=5

Figure 10: Atomic force microscopy imaging and corresponding section analyses of irradiated part of samples. Atomic force microscopy imaging of irradiated part of graphene is shown at fluences (a) 1 × 1013, (c) 3 × 1013 and (e) 1 × 1014 ions/cm2, and corresponding section analyses is shown in (b), (d) and (f), respectively.
Mentions: Atomic force microscopy imaging (Figure 10) also confirms the reduction in number of layers at different places of irradiated samples and shows that at higher fluence (above 1 × 1013 ions/cm2) there is more coverage of one- and two-layer graphene instead of three to four layers observed before irradiation. The ion irradiation-induced ablation in graphene can be used for controlling the number of layers with spatial selectivity. Similar reduction in the number of graphene layers with laser ablation above a given threshold laser energy density has been demonstrated by Dhar et al. [54]. This shows the possibility of manipulating regions with varying number of graphene layers. This spatial selectivity of layers is desirable for engineering the properties for the device applications.

Bottom Line: We report swift heavy ion (SHI) irradiation-induced annealing and purification effects in graphene films, similar to that observed in our studies on fullerenes and carbon nanotubes (CNTs).This indicates that SHI induces annealing effects at lower fluences.The results suggest that SHI irradiation fluence may be used as one of the tools for defect annealing and manipulation of the number of graphene layers. 60.80.x; 81.05.ue.

View Article: PubMed Central - HTML - PubMed

Affiliation: Materials Science Group, Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067, India.

ABSTRACT

Unlabelled: Studies on interaction of graphene with radiation are important because of nanolithographic processes in graphene-based electronic devices and for space applications. Since the electronic properties of graphene are highly sensitive to the defects and number of layers in graphene sample, it is desirable to develop tools to engineer these two parameters. We report swift heavy ion (SHI) irradiation-induced annealing and purification effects in graphene films, similar to that observed in our studies on fullerenes and carbon nanotubes (CNTs). Raman studies after irradiation with 100-MeV Ag ions (fluences from 3 × 10(10) to 1 × 10(14) ions/cm(2)) show that the disorder parameter α, defined by I D/I G ratio, decreases at lower fluences but increases at higher fluences beyond 1 × 10(12) ions/cm(2). This indicates that SHI induces annealing effects at lower fluences. We also observe that the number of graphene layers is reduced at fluences higher than 1 × 10(13) ions/cm(2). Using inelastic thermal spike model calculations, we estimate a radius of 2.6 nm for ion track core surrounded by a halo extending up to 11.6 nm. The transient temperature above the melting point in the track core results in damage, whereas lower temperature in the track halo is responsible for annealing. The results suggest that SHI irradiation fluence may be used as one of the tools for defect annealing and manipulation of the number of graphene layers.

Pacs: 60.80.x; 81.05.ue.

No MeSH data available.


Related in: MedlinePlus