Investigations on self-organization and nucleation of meta-stable bismuth oxide polymorphs

亚稳氧化铋多晶型物的自组织和成核研究

• 批准号: 141805253
• 负责人: Professor Dr. Michael Mehring
• 金额: --
• 依托单位: Institut für Chemie
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/141805253?language=en
• 关键词: Investigations; self; organization; nucleation; meta

The experiments carried out so far within SPP 1415 are based on a combined experimental and theoretical approach and gave a first insight into the nucleation, stability and mechanism of formation for bismuth oxido clusters. The bismuth oxido clusters serve as starting materials for the synthesis of crystalline motifs of metastable bismuth oxides. The studies in terms of formation of bismuth oxide polymorphs and the underlying mechanisms will be extended in the forthcoming period. The use of additives, which are capable of cluster stabilization, and the variation of reaction conditions will give access to parameters that control the growth of bismuth oxido clusters and thus the formation of bismuth oxide polymorphs. Ion mobility mass spectrometry and ESI mass spectrometry will provide in situ information about the process of nucleation in solution and about the influence of additives. In addition DOSY-NMR, light scattering experiments and especially in situ synchrotron scattering and PXRD experiments will be carried out. The first steps of crystallization from solution will be identified and the growth mechanisms will be studied. The experiments regarding cluster growth and the process of nucleation will be complementary studied by molecular dynamics simulations in order to get deeper insight into the fundamental processes on a molecular scale. The formation of bismuth oxido clusters of various size as well as condensation processes leading finally to bismuth oxide will be modeled. Flash lamp annealing and plasma processing of bismuth oxido clusters under non-equilibrium conditions might offer access to novel metastable bismuth oxides. Additionally, the high reactivity of stabilized β-Bi2O3 nanoparticles will be used to prepare metastable homo- and heterometallic bismuth oxides, e.g. by mechanochemical synthesis.

到目前为止，在SPP 1415内进行的实验是基于实验和理论相结合的方法，并给出了第一个洞察的成核，稳定性和形成机制的氧化铋团簇。氧化铋团簇作为起始材料用于合成亚稳氧化铋的晶体图案。在今后一段时间内，将扩大对氧化铋多晶型物的形成及其基本机制的研究。使用能够稳定团簇的添加剂和改变反应条件将获得控制氧化铋团簇生长并因此形成氧化铋多晶型物的参数。离子迁移率质谱和ESI质谱将提供有关溶液中成核过程和添加剂影响的原位信息。此外，还将进行DOSY-NMR、光散射实验，特别是原位同步辐射散射和PXRD实验。将确定从溶液中结晶的第一步，并研究生长机制。有关团簇生长和成核过程的实验将通过分子动力学模拟进行补充研究，以便更深入地了解分子尺度上的基本过程。将模拟各种尺寸的氧化铋团簇的形成以及最终导致氧化铋的冷凝过程。闪光灯退火和等离子体处理的氧化铋团簇在非平衡条件下可能会提供新的亚稳态氧化铋。此外，稳定的β-Bi 2 O3纳米颗粒的高反应性将用于制备亚稳的均金属和异金属铋氧化物，例如通过机械化学合成。