Surface structure modification of ReSe₂ nanosheets via carbon ion irradiation

Abstract

The effects of C ion irradiation on multilayer ReSe2 flakes are studied by utilizing different kinds of technologies. The domain sizes, thickness, morphologies of the multilayer ReSe2 flakes on the Al2O3 substrates before and after 1.0-MeV C ion irradiation with different fluence rates are studied by atomic force microscope and scanning electron microscopy. The atomic vibrational spectra of multilayer ReSe2 flakes are detected by micro-Raman spectra. The redshifts of the Raman modes after 1.0-MeV C ion irradiation are observed from the micro-Raman spectra. The elemental compositions and bonding configurations of the multilayer ReSe2 samples before and after irradiation processes are characterized by x-ray photoelectron spectroscopy. The structural properties are also investigated by x-ray diffraction, and it is concluded that after 1.0-MeV C ion irradiation process, multilayer ReSe2 samples continue to grow on Al2O3 substrates, the increase of crystallite size also reveals that the crystallinity is improved with the increase of the layer number after 1.0-MeV C ion irradiation.