A photoluminescence study of REE3+ emissions in radiation-damaged zircon
A photoluminescence study of REE3+ emissions in radiation-damaged zircon
复制标题
辐射损伤锆石中 REE3 发射的光致发光研究
DOI：
10.2138/am-2015-4894ccbyncnd
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发表时间：
2015
影响因子：
3.1
通讯作者：
L. Nasdala
中科院分区：
文献类型：
--
作者：
C. Lenz;L. Nasdala
本文用REE3+光致发光光谱研究了一系列天然锆石样品(铀浓度为140-2600ppm，从结晶良好到严重辐射损伤)。我们发现REE3+发射的系统性变化依赖于有效的时间积分a剂量的锆石样品所表示的累积辐射损伤。由于干退火引起的结构重组导致了强度的增加和REE3+发射的半宽减小。Dy3+的4F9/2→6H13/2跃迁(~17250 cm-1；~580 nm波长)和Nd3+的4F3/2→4I9/2跃迁(~11300 cm-1；~885 nm波长)的不同发光斯塔克能级的谱带半宽度与累积的辐射损伤程度密切相关。这些REE3+的发射被认为是辐射引起的锆石结构无序的潜在量度。这两种发射被认为特别合适，因为(1)它们通常在天然锆石的光致发光光谱中被检测到，(2)它们几乎不受其他发射或斯塔克水平的影响。使用一套表征良好的斯里兰卡锆石建立了将带宽增加与a剂量相关的初步校准曲线。随着粒子自辐照的增加，谱带展宽被归因于结构破坏的增加，即REE3+阳离子晶格位置的扰动增加。讨论了REE3+发光光谱作为拉曼光谱的补充，作为定量结构辐射损伤的方法的可能优势。
Abstract A series of natural zircon samples (with U concentrations of 140-2600 ppm and ranging from well crystalline to severely radiation damaged) were investigated by means of REE3+ photoluminescence spectroscopy. We found systematic changes in REE3+ emissions depending on the accumulated radiation damage expressed by the effective time-integrated a-dose of zircon samples. Structural reconstitution as caused by dry annealing resulted in intensity gains and decreases of half-widths of REE3+ emissions. The band half-widths of distinct luminescence Stark’s levels of the 4F9/2 → 6H13/2 transition of Dy3+ (~17 250 cm-1; ~580 nm wavelength) and the 4F3/2 → 4I9/2 transition of Nd3+ (~11 300 cm-1; ~885 nm wavelength) were found to correlate sensitively with the degree of radiation damage accumulated. These REE3+ emissions are proposed as potential measure of the irradiation-induced structural disorder of zircon. The two emissions are considered particularly suitable because (1) they are commonly detected in PL spectra of natural zircon, and (2) they are hardly biased by other emissions or Stark’s levels. Preliminary calibration curves that relate band-width increases to the a dose were established using a suite of well-characterized Sri Lankan zircon. Band broadening upon increasing corpuscular self-irradiation is assigned to increasing structural destruction, i.e., the increasing perturbation of REE3+ cationic lattice sites. Possible advantages of REE3+ luminescence spectroscopy, complementary to Raman spectroscopy, as method to quantify structural radiation damage are discussed.