Exfoliated graphite with graphene flakes as potential candidates for TL dosimeters at high gamma doses

Graphite powder (GP) subjected to microwave radiation (MWG) results in exfoliation of graphite particles into few-layered graphene flakes (GF) intermixed with partially exfoliated graphite particles (PEG). Characterization of MWG by Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and Raman spectroscopy reveal few-layer GF with sizes ranging from 0.2 to 5 µm. Raman D, G, and 2D (G′) bands characteristic of graphitic structures include evidence of the presence of bilayered graphene. The thermoluminescent (TL) dosimetric properties of MWG are evaluated and can be characterized as a gamma-ray sensitive and dose-resistant material with kinetic parameters (activation energy for the main peak located at 400 and 408 K is 0.69 and 0.72 eV) and threshold dose (~1 kGy and 5 kGy respectively). MWG is a low-Z material (Zeff = 6) with a wide linear range of TL dose-response (0.170–2.5 kGy) tested at doses in the 1–20 kGy range with promising results for applications in gamma-ray dosimetry. Results obtained in gamma irradiated MWG are compared with those obtained in graphite powder samples (GP) without microwave treatment. •Single Wall Carbon Nanotubes (SWNT) as potential material for use as detector phosphor for gamma radiation.•Gamma irradiation of SWNT induced changes on the morphology of the SWNT, such as nanoloops.•TL properties of SWNT synthesized by the hydrogen arc plasma jet method reveals like sensitive and dose-resistant material.