Mir Anamul H, Hinks J A, Delaye Jean-Marc, Peuget Sylvain, Donnelly S E
Electron Microscopy and Materials Analysis, School of Computing and Engineering, University of Huddersfield, Queensgate, Huddersfield, HD1 3DH, United Kingdom.
CEA, DEN, Laboratoire d'Étude des Matériaux et Procédés Actif, 30207, Bagnols-sur-Cèze, France.
Sci Rep. 2018 Oct 17;8(1):15320. doi: 10.1038/s41598-018-33556-y.
Estimates of noble gas solubility in glasses and minerals are important to understand the origin of these gases, particularly xenon, in the atmosphere. However, technical difficulties and ambiguities in quantifying the dissolved gases introduce large uncertainties in the solubility estimates. We present here the use of transmission electron microscopy (TEM) with in-situ noble gas ion implantation as a non-equilibrium approach for noble gas solubility estimates. Using a suitable Xe equation of state and Monte-Carlo simulations of TEM images, a clear distinction between Xe filled precipitates and empty voids is made. Furthermore, implantation-induced changes in the solubility are estimated using molecular dynamics simulations. These studies allow us to evaluate the xenon solubility of irradiated and pristine silica glasses and monitor in-situ the diffusion-mediated dynamics between the precipitates and voids - otherwise impossible to capture. On exceeding the solubility limit, supercritical xenon precipitates, stable at least up to 1155 K, are formed. The results highlight the high capacity of silicates to store xenon and, predict higher solubility of radiogenic xenon due to the accompanying radiation damage.
估算稀有气体在玻璃和矿物中的溶解度对于理解这些气体，尤其是大气中氙气的起源至关重要。然而，在量化溶解气体方面的技术难题和模糊性给溶解度估算带来了很大的不确定性。我们在此展示了使用透射电子显微镜（TEM）结合原位稀有气体离子注入作为一种非平衡方法来估算稀有气体的溶解度。利用合适的氙状态方程和TEM图像的蒙特卡罗模拟，能够清晰区分充满氙的沉淀物和空的孔隙。此外，使用分子动力学模拟估算注入引起的溶解度变化。这些研究使我们能够评估辐照过的和原始二氧化硅玻璃的氙溶解度，并原位监测沉淀物和孔隙之间扩散介导的动力学——否则这是无法捕捉到的。当超过溶解度极限时，会形成超临界氙沉淀物，至少在1155 K时是稳定的。结果突出了硅酸盐储存氙的高能力，并预测由于伴随的辐射损伤，放射性氙的溶解度会更高。
