Glass Surface Chemistry - Understanding Effects of Alkali Ions on Water Activity on Glass

玻璃表面化学 - 了解碱离子对玻璃水活度的影响

• 批准号: 1207328
• 负责人: Seong Kim
• 金额: $ 36.43万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-05-01 至 2016-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1207328&HistoricalAwards=false
• 关键词: Glass; Surface; Chemistry; Understanding; Effects

NON-TECHNICAL DESCRIPTION: Although multicomponent silicate glasses are involved in a variety of advanced technical applications, little is known about its surface chemistry in humid ambience. Thus, researchers, engineers and manufacturers must rely on literature and analytical methods relevant to amorphous silica to understand complex glasses even though it is clear that the surface chemistry of multicomponent silicate is quite different than silica. It is the thesis of this study that the structure and reaction of water films on silicate glasses are a function of the glass surface composition as well as the process through which the surface is created and the presence of applied or residual surface stress. This study consists of a series of carefully-designed experiments to test this hypothesis. The outcome of this research will benefit not only the glass science field, but also other engineering technologies, manufacturing, and life science research. Considering the broad range of engineering and science technologies that work with glass, it is an ideal medium through which to educate the broader community about materials, in general. This research is being integrated with education by participating in a summer Research Experiences for Undergraduates (REU) program, delivering short courses at a historically black university, mentoring undergraduate students as well as underrepresented minority students on research projects, and introducing young women from high school into research.NON-TECHNICAL DESCRIPTION: The over-arching hypotheses of this study are: (1) the presence of local stress, whether intrinsic, applied, residual or due to local atomic/molecular structure, is a factor in determining the water layer structure, its adhesion and its reactivity, and (2) water molecules on multicomponent silicate glasses form a highly-structured interfacial layer, including hydration of metal ions, which acts as an integral part of the glass surface. Non-linear laser spectroscopy and advanced thermodynamic measurements are being used to directly measure the thickness, structure and energy of the chemisorbed as well as physisorbed water layer on multicomponent glass surfaces with varying concentrations of alkali ions. This information about the adsorbed water layer is being related to the adhesion and friction-induced dissolution of multicomponent glass surfaces in humid ambience.

非技术描述：尽管多种成分硅玻璃涉及多种先进的技术应用，但对其在潮湿的氛围中的表面化学反应知之甚少。因此，研究人员，工程师和制造商必须依靠与无定形二氧化硅相关的文献和分析方法来了解复杂的玻璃，即使很明显，多组分硅酸盐的表面化学与二氧化硅的表面化学完全不同。这项研究的论点是，硅酸盐玻璃上的水膜的结构和反应是玻璃表面组成的函数，以及产生表面的过程以及施加或残留的表面应力的存在。这项研究包括一系列精心设计的实验，以检验该假设。这项研究的结果不仅将使玻璃科学领域，而且使其他工程技术，制造业和生命科学研究受益。考虑到与玻璃一起使用的各种工程和科学技术，它是一种理想的媒介，可以通过它来教育更广泛的社区有关材料的教育。这项研究通过参加夏季研究经验（REU）计划，在历史悠久的黑人大学提供短期课程，指导本科生以及代表性不足的少数群体从事研究项目，并从高中介绍研究。或由于局部原子/分子结构，是确定水层结构，其粘附和反应性的一个因素，以及（2）多组分硅酸盐玻璃上的水分子形成了高度结构的界面层，包括金属离子的水合，这些金属离子是玻璃表面的积分部分。非线性激光光谱和先进的热力学测量被用于直接测量化学吸附剂的厚度，结构和能量，以及在多组分玻璃表面上具有不同浓度碱基离子的多组分玻璃表面上的物理水层。 有关吸附水层的此信息与潮湿氛围中多组分玻璃表面的粘附和摩擦引起的溶解有关。