Imaging charge transfer dynamics in nanomaterials using electron donor/acceptor modified AFM tips

在这个奖项中，由化学系的化学测量和成像计划资助，埃默里大学的Tianquan Lian教授和他的博士后，研究生和本科生研究人员将被支持调查使用特别修改的原子力显微镜（AFM）尖端成像纳米材料中电荷转移动力学的可行性。 Lian教授和他的研究小组将把量子点连接到AFM针尖上，并测量修饰后的针尖和探测表面之间的光致电荷转移。 本研究的目的是发展一个更好的理解发生在太阳能转换中使用的纳米材料的边界的物理过程。原子力显微镜方法使用纳米尺度的探针和表面之间的接触来测量被探测表面的形态变化。 探针能够测量纳米（或更小）长度尺度下的下伏表面的物理性质（例如硬度、柔软度）的差异。 Lian教授和他的团队正试图建立一种AFM探针，该探针将能够做AFM所做的事情，除了通过测量改性探针尖端和底层表面之间的光致电荷转移速率的差异。 我们的目标是开发测量纳米材料的物理/电学特性的能力，其分辨率与AFM方法相同。 从事该项目的学生将获得开发尖端分析光谱工具的有用经验，这些工具将有助于评估和表征技术上有用的材料。 作为这项工作的一部分，廉教授将继续他的示范性努力，鼓励学生从代表性不足的群体追求事业的科学。

In this award, funded by the Chemical Measurement and Imaging Program of the Division of Chemistry, Professor Tianquan Lian of Emory University and his postdoctoral, graduate and undergraduate student researchers will be supported to investigate the feasibility of imaging charge transfer dynamics in nanomaterials using specially modified atomic force microscopy (AFM) tips. Prof. Lian and his research group will attach quantum dots to the AFM tips and will measure the photoinduced charge transfer between the modified tip and the probed surface. The goal of this research is to develop a better understanding of the photophysical process taking place at the boundaries in nanomaterials used in solar energy conversion.Atomic force microscopy methods use contact between a nanometer-scale probe and a surface to measure the changes in morphology of the probed surface. The probe is able to measure differences in the physical properties (e.g. hardness, softness) of the underlying surface at the nanometer (or smaller) length scale. Prof. Lian and his group are attempting to build an AFM probe that will be able to do what the AFM does, except by measuring differences in the rate of photoinduced charge transfer between the modified probe tip and the underlying surface. The goal is to develop the ability to measure the photophysical/electrical properties of nanoscale materials with the same resolution that can be obtained with AFM methods. The students working on this project will gain useful experience in developing cutting-edge analytical spectroscopy tools that will be useful for evaluating and characterizing technologically useful materials. As part of this work, Prof. Lian will continue his exemplary efforts at encouraging students from underrepresented groups to pursue careers in the sciences.