International Collaboration in Chemistry: Novel Instrumentation for Modern Elemental Speciation Analysis

固体的表面组成对其化学、物理和材料性质有着深远的影响。这是因为许多重要的现象(如光学相互作用、电子转移等)因此，阐明表面层的组成对于了解一系列化学和物理行为以及指导新材料的结构至关重要。这项建议的目的是继续开发一种能够提供新的表面分析能力的新的、简单的、通用的和相对/廉价的分析仪器。具体地说，该仪器采用原子发射光谱分析(AES)，以三维空间分辨率对固体材料进行元素分析。一种新颖的脉冲辉光放电(GD)被用来从导电、半导体或绝缘体样品的表面溅射原子，然后激发它们被俄歇电子能谱检测。GD通过逐步溅射表面材料和分析组成原子来提供纳米分辨率的表面深度剖面分析。脉冲GD通过限制AgAs相原子在被激发和检测之前从它最初被溅射的点开始的距离来提供横向空间分辨率。这种新颖的GD-AES分析的最终结果是揭示固体样品中原子的位置、类型和数量的三维(3-D)多元素发射图。在先前NSF和DFG的支持下进行的研究已经验证了这种工具的可行性。有关更多细节，例如在生物分子和结构材料分析中的应用，请参阅申请的NSF部分。

The surface composition of a solid has a profound influence on its chemical, physical and material properties. This is because many important phenomena (e.g. optical interaction, electron transfer, etc.) are localized at the solid interface; thus, elucidating the composition of the surface layers is crucial to understanding a host of chemical and physical behaviors, as well as informing the construction of new materials. The aim of this proposal is the continued development of a novel, simple, general, and relativer/ inexpensive analytical instrument capable of providing new surface analysis capabilities. Specifically, the instrument employs atomic-emission spectrometry (AES) for the elemental analysis of solid materials with three dimensional spatial resolution. A novel pulsed glow discharge (GD) is used to sputter atoms from the surface of conductive, semiconductor, or insulator samples, and subsequently excite them to be detected by AES. The GD provides depth-profiling analysis of the surface with nanometer resolution by progressively sputtering away surface material and analyzing the constituent atoms. The pulsed GD provides lateral spatial resolution by restricting the distance agas-phase atom travels from the point from which it was initially sputtered before it is excited and detected. The ultimate result of this novel GD-AES analysis is then a 3-dimensional (3-D) multi elemental emission map revealing the location, type, and quantity of atoms within the solid sample. Studies conducted under prior NSF and DFG support have verified the viability of such an instrument. For further details, e.g. applications in biomolecule and structured materials analyses, see NSF part of the application.