摘要
Al_2O_3∶C单晶具有优良的热释光特性,被用做热释光剂量计,但α-Al_2O_3∶C晶体剂量计的形状不易加工,生产成本高且碳在晶体中难以掺杂均匀。采用低温燃烧合成法以无水乙醇为溶剂,尿素为染料,硝酸铝为反应物制备少团簇、分散均匀的片状α-Al_2O_3∶C陶瓷粉体。探讨不同点火温度和不同退火温度对其光致发光特性的影响,不同退火温度对热释光特性的影响以及热释光与辐射剂量(^(90)Srβ)的关系。通过分析α-Al_2O_3∶C陶瓷粉体的光致发光光谱得出:α-Al_2O_3∶C陶瓷粉体的发射波长在395nm附近,点火温度T≤800℃时,点火温度为500℃制备的α-Al_2O_3∶C陶瓷粉体的光致发光强度最强;在相同点火温度T=500℃下,经不同温度退火制备α-Al_2O_3∶C陶瓷粉体,点火温度为500℃制备的α-Al_2O_3∶C陶瓷粉体经1 000℃退火后光致发光强度最强。通过分析α-Al_2O_3∶C陶瓷粉体的热释光曲线得出:退火后的α-Al_2O_3∶C陶瓷粉体在200℃左右的热释光峰值占主导,900℃退火的α-Al_2O_3∶C陶瓷粉体在200℃附近的热释光峰值最强;通过峰高法对900℃高温退火处理后的α-Al_2O_3∶C陶瓷粉体位于200℃左右的热释光峰做剂量响应曲线,可以看出,在1~50Gy剂量范围内具有良好的热释光剂量线性响应关系,在50~200Gy剂量范围内出现超线性响应关系。与α-Al_2O_3∶C晶体(1~10Gy)和多孔Al_2O_3∶C薄膜(1~10Gy)相比,α-Al_2O_3∶C陶瓷粉体的线性剂量响应范围明显扩大。此研究可为提高氧化铝陶瓷粉体的热释光性能提供思路。
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 requiressophisticated laboratories,high temperatures and highly reducing atmosphere and their manufacturing cost is high.Furthermore,carbon is difficult to dopeevenly in crystals.In this paper,flakyα-Al2O3∶C ceramic powder withuniform dispersion and few clusters are prepared by using the low temperaturecombustion 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 ofα-Al2O3∶C ceramic powder and discussed the TL dose response.Through analyzing the photoluminescence spectra ofα-Al2O3∶C ceramic powders,itwas found that the emission wavelength ofα-Al2O3∶C ceramic powder is about 395 nm.When the ignition temperature T≤800℃,the PL intensity ofα-Al2O3∶C ceramic powder reaches a maximum value at ignition temperature of500℃.At the same ignition temperature T=500℃,α-Al2O3∶C ceramic powders were prepared by annealing at different temperatures.The results show thatα-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 ofα-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℃bypeak height method through selecting the dominant thermoluminescence peak at about 200℃.It was found that the TL response of theα-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 withα-Al2O3∶C crystal(1~10 Gy)and porous alumina membranes(1~10 Gy)
作者
皇环环
王倩
吴丽
李梦晓
HUANG Huan-huan;WANG Qian;WU Li;LI Meng-xiao(School of Physics Science and Technology,Xinjiang University,Urumqi 830046, China)
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2018年第9期2676-2680,共5页
Spectroscopy and Spectral Analysis
基金
国家自然科学基金项目(11765022)
新疆研究生科研创新项目(XJGRI2016007)资助
关键词
氧化铝陶瓷粉体
光致发光
热释光
Alumina ceramic powders
Photoluminescence
Thermoluminnescence
