In Situ Transmission Electron Microscopy Explores a New Nanoscale Pathway for Direct Gypsum Formation in Aqueous Solution
In Situ Transmission Electron Microscopy Explores a New Nanoscale Pathway for Direct Gypsum Formation in Aqueous Solution
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DOI：
10.1021/acsanm.8b00739
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发表时间：
2018-10-01
影响因子：
5.9
通讯作者：
Shahbazian-Yassar, Reza
中科院分区：
文献类型：
--
作者：
He, Kun;Nie, Anmin;Shahbazian-Yassar, Reza
在现代建筑工业中，大型石膏（CaSO4中心点2H(2)O）板的制造是通过两步工艺进行的，其特点是将细石膏粉加热形成中间石膏（巴萨石，CaSO4中心点0.5H(2)O），然后中间相水化形成最终成型产品。在这里，我们探索了一种制造石膏微针的新途径，该途径绕过了中间玄武岩相的形成。利用原位液体透射电子显微镜，在纳米尺度上实时研究了细石膏粉在硫酸钙溶液中的动态行为。在石膏纳米颗粒直接转化为石膏微针的过程中，取向附着机制起主导作用，其中不涉及中间相。我们的实验结果促进了对石膏和水之间动态相互作用的基本理解。提出的纳米尺度的石膏进化途径可能会彻底改变植根于石膏板制造的建筑行业，因为它承诺了一种时间和节能的大规模生产过程。此外，这项工作还可以激发地质学、考古学和生物学等相关领域的研究，这些领域的历史意义往往是从与石膏有关的发现中推断出来的。
In the modern construction industry, large gypsum (CaSO4 center dot 2H(2)O) boards are manufactured through a two-step procedure, which features the heating of fine gypsum powders to form the intermediate plaster of Paris (bassanite, CaSO4 center dot 0.5H(2)O) followed by hydration of the intermediate phase to form the final formed product. Here, we explore a novel pathway toward the fabrication of gypsum microneedles that bypasses formation of the intermediate bassanite phase. Using in situ liquid transmission electron microscopy, the dynamic behavior of fine gypsum powders in a calcium sulfate solution is investigated at the nanoscale and in real time. An oriented-attachment mechanism is found to dominate the direct transformation of gypsum nanoparticles to gypsum microneedles, where no intermediate phases are involved. Our experimental results advance the fundamental understanding of the dynamic interactions between gypsum and water. The proposed nanoscale pathway for gypsum evolution could potentially revolutionize the construction industry rooted in gypsum board manufacturing by promising a time- and energy-efficient mass production procedure. In addition, this work can inspire research efforts associated with geology, archeology, and biology, where historical significance is frequently deduced from gypsum-related discoveries.