Abstract:α-Al2O3∶C crystals possess high thermoluminescence (TL) sensitivity and have been widely used as thermoluminescence dosimeters, however, α-Al2O3∶C crystals dosimeter’s shape is not easy to process, the crystals growth requires sophisticated laboratories, high temperatures and highly reducing atmosphere and their manufacturing cost is high. Furthermore, carbon is difficult to dope evenly in crystals. In this paper, flaky α-Al2O3∶C ceramic powder with uniform dispersion and few clusters are prepared by using the low temperature combustion synthesis method, with aluminum nitrate as reactant, urea as dye, anhydrous ethanol as solvent. We have investigated the influence of ignition temperature and annealing temperature on photoluminescence (PL) as well as TL characteristics of α-Al2O3∶C ceramic powder and discussed the TL dose response. Through analyzing the photoluminescence spectra of α-Al2O3∶C ceramic powders, it was found that the emission wavelength of α-Al2O3∶C ceramic powder is about 395 nm. When the ignition temperature T≤800 ℃,the PL intensity of α-Al2O3∶C ceramic powder reaches a maximum value at ignition temperature of 500 ℃. At the same ignition temperature T=500 ℃, α-Al2O3∶C ceramic powders were prepared by annealing at different temperatures. The results show that α-Al2O3∶C ceramic powder prepared at the ignition temperature of 500 ℃ has the greatest PL intensity after annealing at 1 000 ℃. Through the analysis on the thermoluminescence curve of α-Al2O3∶C ceramic powder,it can be seen that the sample annealed at 900 ℃ has the greatest TL glow peak at ~200 ℃. The dose response curve is made for the sample annealed at 900 ℃ by peak height method through selecting the dominant thermoluminescence peak at about 200 ℃. It was found that the TL response of the α-Al2O3∶C ceramic powders annealed at 900 ℃ shows excellent linear characteristic within a dose range of 1~50 Gy, but shows super-linear behavior in a dose range of 50~200 Gy. Compared with α-Al2O3∶C crystal (1~10 Gy) and porous alumina membranes (1~10 Gy), TL response of α-Al2O3∶C ceramic powder shows a wider range of linear dose response. This study will provide a way to improve the thermoluminescence properties of alumina ceramic powder.
皇环环,王 倩,吴 丽,李梦晓. 低温燃烧合成法制备的氧化铝陶瓷粉体的发光特性[J]. 光谱学与光谱分析, 2018, 38(09): 2676-2680.
HUANG Huan-huan, WANG Qian, WU Li, LI Meng-xiao. The Luminescence Characteristics of Alumina Ceramic Powder by the Low Temperature Combustion Synthesis. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2018, 38(09): 2676-2680.