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arXiv · 1109.1483

Irradiation Enhanced paramagnetism on graphene nanoflakes

Andreas Ney·Pagona Papakonstantinou·Ajay Kumar·Nai-Gui Shang·Nianhua Peng
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Abstract

We have studied the magnetization of vertically aligned graphene nanoflakes irradiated with nitrogen ions of 100 KeV energy and doses in the range 10^11- 10^17 ions/cm2. The non-irradiated graphene nanoflakes show a paramagnetic contribution, which is increased progressively by ion irradiation at low doses up to 10^15 /cm^2. However, further increase on implantation dose reduces the magnetic moment which coincides with the onset of amorphization as verified by both Raman and X-ray photoelectron spectroscopic data. Overall, our results demonstrate the absence of ferromagnetism on either implanted or unimplanted samples from room temperature down to a temperature of 5K

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Andreas Ney, Pagona Papakonstantinou, Ajay Kumar, Nai-Gui Shang, Nianhua Peng. 2011-09-07. Irradiation Enhanced paramagnetism on graphene nanoflakes. https://doi.org/10.1063/1.3628245

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