CAREER: Advancing Mechanistic Understanding of Nanocrystal Dissolution in Aqueous Environments

纳米材料在水中的溶解是各种化学过程的组成部分，包括腐蚀、降解、分解和催化。然而，温度、溶液pH和化学、静电势、晶体尺寸和形态、结构缺陷以及检测短寿命反应中间体的挑战等因素限制了我们对溶解机制的理解。在这项提议中，主要研究者的目标是建立几种材料类别的溶解机制途径和速率，主要目标是使用计算技术提供溶解过程的统一图像。这一新的认识将有助于确定实验假设的机制，提出推动溶解反应沿着优选路线的环境条件，并有助于设计不易溶解的材料。研究结果将纳入工程课程，并将组织一个夏季讲习班，培训高中教师有关计算材料科学的主题。本研究旨在建立纳米尺度下材料溶解的理论基础，利用完全的量子力学模拟，通过热力学和动力学研究的紧密结合，提供溶解现象的完整图景。纳米颗粒溶解的实验研究是相当具有挑战性的，因为这一瞬态过程在很大程度上取决于多个相互关联的因素。pi建议使用能够采样统计罕见事件的原子模拟，这将使人们能够在良好控制的条件下在单个事件水平上了解溶解。所提出的活动的结果将是通过利用第一性原理理论/计算方法来基本理解控制纳米材料界面行为的分子机制。了解材料的稳定性和活性之间的基本联系，有望通过选择性溶解/蚀刻来有效和合理地设计新材料，以提高催化剂的性能。本提案教育部分的目标是将合作小组学习策略作为一种有效的解决问题的教学方法实施到UNL的工程课程中，并评估其对学生学习和团队合作技能的影响。内布拉斯加州大学林肯分校的首席研究员将与内布拉斯加州教育部合作，举办一所综合材料教育暑期学校，对高中教师进行理论、模拟和科学计算工具方面的培训，目标是开发可纳入内布拉斯加州高中课程的教学材料，以吸引学生进入STEM职业。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Nanomaterial dissolution in water is integral to a variety of chemical processes including corrosion, degradation, decomposition and catalysis. However, several factors including temperature, solution pH and chemistry, electrostatic potential, crystallite size and morphology, structural defects and the challenge of detecting short-lived reaction intermediates limit our understanding of dissolution mechanisms. In this proposal, the principal investigator aims to establish mechanistic pathways and rates of dissolution across several materials classes with the primary goal of providing a unified picture of the dissolution process using computational techniques. This new understanding will help identify experimentally hypothesized mechanisms, suggest ambient conditions to drive dissolution reactions along preferable routes, and aid the design of materials less prone to dissolution. The research results will be integrated into the engineering curriculum and a summer workshop will be organized to train high-school teachers on topics related to computational materials science.This proposal aims to develop a theoretical foundation of materials dissolution at the nanoscale by employing fully quantum-mechanical simulations to provide a complete picture of dissolution phenomenon through a tight integration of thermodynamic and kinetic studies. Experimental studies of nanoparticle dissolution are rather challenging as this transient process depends strongly on multiple interrelated factors. The PIs propose to use atomistic simulations capable of sampling statistically rare events which will enable insights into dissolution at a single event level under well controlled conditions. The outcome of the proposed activities will be fundamental understanding molecular mechanisms controlling interfacial behavior of nanomaterials by utilizing first-principles theoretical/computational approaches. Understanding the fundamental link between stability and activity of materials is expected to lead to efficient and rational design of new materials via selective dissolution/etching for improving catalyst performance. The goal of the education part of this proposal is to implement cooperative group learning strategy as an efficient problem-solving instructional approach into the engineering curriculum at UNL and evaluate its impact on student learning and teamwork skills. A summer school on integrated materials education will be hosted by the principal investigator at the University of Nebraska-Lincoln, in collaboration with the Nebraska Department of Education, to train high-school teachers on theory, simulation and scientific computing tools with the goal of developing instructional material that can be integrated into the curriculum of Nebraska high schools to attract students into STEM careers.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.