Developing Atom Probe Tomography of Phyllosilicates in Preparation for Extra-Terrestrial Sample Return
Developing Atom Probe Tomography of Phyllosilicates in Preparation for Extra-Terrestrial Sample Return
复制标题
开发层状硅酸盐原子探针断层扫描技术，为外星样本返回做准备
DOI：
10.1111/ggr.12382
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发表时间：
2021
影响因子：
3.8
通讯作者：
Daly L
中科院分区：
文献类型：
--
作者：
Daly L
含水层状硅酸盐矿物，包括蛇纹岩亚群，很可能是火星任务和原始小行星龙宫和本奴带回地球的材料的主要成分。少量（< 60克）微米尺寸的内部非均质材料将可用于研究，需要最小破坏性技术。许多传统的方法不适合层状硅酸盐，因为它们通常是精细结晶和电子束敏感的，导致无定形和脱水。将需要新的工具来对这些珍贵的地外样本进行纳米级表征。在这里，我们测试了原子探针断层扫描（APT）的有效性。使用来自西班牙Ronda橄榄岩的蜥蜴石作为陆地类似物，我们概述了一种有效的分析方案，以提取层状硅酸盐的纳米级化学和结构测量。APT的潜力被意想不到的发现所证明，Ronda lizardite含有富含sio2的纳米相，与作为橄榄石蛇纹石化副产物形成的蛋白石二氧化硅相一致。由于更成熟的成像技术的分辨率限制，我们的新APT方法解锁了层状硅酸盐中以前无法观察到的纳米矿物和纳米结构。APT将对地球、火星和原始小行星上的水/岩石相互作用的过程和产物提供独特的见解。
Hydrous phyllosilicate minerals, including the serpentine subgroup, are likely to be major constituents of material that will be bought back to Earth by missions to Mars and to primitive asteroids Ryugu and Bennu. Small quantities (< 60 g) of micrometre‐sized, internally heterogeneous material will be available for study, requiring minimally destructive techniques. Many conventional methods are unsuitable for phyllosilicates as they are typically finely crystalline and electron beam‐sensitive resulting in amorphisation and dehydration. New tools will be required for nanoscale characterisation of these precious extra‐terrestrial samples. Here we test the effectiveness of atom probe tomography (APT) for this purpose. Using lizardite from the Ronda peridotite, Spain, as a terrestrial analogue, we outline an effective analytical protocol to extract nanoscale chemical and structural measurements of phyllosilicates. The potential of APT is demonstrated by the unexpected finding that the Ronda lizardite contains SiO‐rich nanophases, consistent with opaline silica that formed as a by‐product of the serpentinisation of olivine. Our new APT approach unlocks previously unobservable nanominerals and nanostructures within phyllosilicates owing to resolution limitations of more established imaging techniques. APT will provide unique insights into the processes and products of water/rock interaction on Earth, Mars and primitive asteroids.