Characteristics Research On Radiationinduced Luminescence Of Nano Carbon-doped Alumina Film

Al2O3: C crystal as traditional radiation material has been widely used in the field of radiation dosimetry, and porous alumina film with carbon impurities can be prepared in oxalic acid solution by anodic oxidation, this paper to explore the luminescence mechanism of nano carbon-doped alumina fil m and dosimetry characteristics of the thermoluminescence, optically stimulated luminescence, radioluminescence.Nano carbon-doped alumina films were fabricated by two-step anodic oxidation of aluminum in oxalic acid solution, the surface morphology of the alumina membranes were observed using field emission scanning electron microscope(FESEM), and the results showed that the porous alumina film appeared uniform and orderly pore structure, the aperture between 30 ~ 100 nm. The energy dispersive X ray spectroscopy(EDS) and the Fourier transform infrared spectroscopy(FTIR) measurements showed that oxalic ions were incorporated into the alumina film in the synthesis process and further heating up to 500 ℃ did not cause oxalic ions to completely decompose. For mation mechanism of the nano carbon-doped alumina film analysis indicated that the three kinds of defects which are F+, F and oxalic acid impurity related defects were introduced in the process of preparing thin film. When a wavelength of 330 nm light stimulated the film, a strong photoluminescence peak around 420 nm was arisen, the help of gaussian fitting study indicated that the luminescence were made up of F +, F and oxalic acid impurity related luminescence centers, and F center plays a leading role.The nano carbon-doped alumina film thermoluminescence testing results showed that the samples which was annealed at 500℃ appeared three thermoluminescence peak, at low temperature(80 ℃) and high temperature(310℃), and in 190℃, respectively, the samples appeared two thermoluminescence peak in low temperature and high temperature under other annealing temperature. Samples which was annealed at 600℃ thermoluminescence peak at about 300 ℃ was the strongest. Thermoluminescence dose response was made using the total area below the peak from 200 to 500℃, which indicated a linear TL response with the dose in the range from1 to 10 Gy, but the dose response appeared superlinear with does in the range from 10 to 120 Gy. Optically stimulated luminescence testing results showed that the OSL has the excellent features, the film which was annealed at 600℃ OSL was strongest, and after different temperature annealing the films OSL were good linear response with the dose in the range from 1 to 200 Gy. Radioluminescence properties of the crystal Al2O3:C were simulated numerically, the results can provide some references for further experiments. All of these indicated that the nano carbon-doped alumina film may become a new material in radiation dosimetry field, and to lay a firm foundation for further study.