▎ 摘　　要

Novel 3 dimensional radiation sensors using reduced graphene oxide (rGO) nanoflakes in polymethyl methacrylate matrix as sensing material were synthesized and fabricated to measure the dose rate of gamma radiation. A detailed characterization of the prepared reduced graphene oxide using X-ray diffraction (XRD), thermal gravimetric analysis (TGA), atomic force microscopy (AFM), Field Emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR) and High-resolution transmission electron microscopy (HRTEM) is presented. Reduced graphene oxide-polymethyl methacrylate composite was prepared using methylene chloride solvent-assisted dispersion of nano flakes of reduced graphene oxide in the polymer matrix. The gamma sensor mainly consists of polymethyl methacrylate/reduced graphene oxide (rGO/PMMA) nanocomposite as the sensing material and two silver coated glass electrodes to make a conductive cell. Real time dose rate information of the nanocomposite such as linearity response to dose rate and sensitivity are investigated. rGO/PMMA based gamma sensors show better performance at a standard bias voltage with respect to graphene oxide (GO) dosimeters. The response to dose rate is linear in the range of 50-130 mGy/min and the sensor array can be introduced for gamma radiation application dosimetry in diagnostic activities.