Surface Analytical Investigation on Organic Donor-Acceptor Interfaces

技术：本项目使用表面分析探针研究小分子有机光伏材料中的界面。实验研究的目的是了解界面电子结构和施主-受主界面激子解离的基本情况。主要的实验技术包括X射线光电子能谱、紫外光电子能谱和逆光电子能谱。通过观察光致发光光谱强度的猝灭，测量了施主-受主界面的激子离解。用时间分辨双光子光电子能谱研究了施主-受主界面的电荷转移动力学。用X射线光电子能谱对界面化学进行了研究。用扫描隧道显微镜、原子力显微镜和近场扫描光学显微镜对有机层的形貌进行了表征。该项目还将测试通过表面/界面分析形成的概念，通过制造和表征基于表面分析调查结果制造的简单有机光伏器件。非技术性：该项目解决具有高度技术相关性的材料科学专题领域的基础研究问题。它阐述了对有机光伏的基本理解，有机光伏是可再生和环境友好型能源的重要候选者。该项目的一个主要部分是通过在先进有机材料和装置以及材料表面/界面表征方面的跨学科研究来教育和培训研究生和本科生。该计划的一个重要重点是通过罗切斯特大学为女性提供的预科物理体验等项目，为初中生和高中生提供早期研究机会。

Technical: This project studies the interfaces in small-molecule organic photovoltaic materials using surface analytical probes. The objective of the experimental research is to understand the fundamental aspects of the interface electronic structures and the exciton dissociation at the donor-acceptor interfaces. The main experimental techniques include x-ray photoemission spectroscopy, ultraviolet photoemission spectroscopy, and inverse photoemission spectroscopy. Exciton dissociation at the donor-acceptor interfaces is measured by observing the quenching of the photoluminescence spectroscopy intensity. The charge transfer dynamics across the donor-acceptor interfaces is investigated with time-resolved two-photon photoemission spectroscopy. X-ray photoemission spectroscopy is used to study the interface chemistry. The morphology of the organic layers is characterized with scanning tunneling microscopy, atomic force microscopy, and near-field scanning optical microscopy. The project will also test the concepts developed through the surface/interface analysis by fabricating and characterize simple organic photovoltaic devices fabricated based on the findings of surface analytical investigations.Non-technical: The project addresses basic research issues in a topical area of materials science with high technological relevance. It addresses fundamental understanding of organic photovoltaics, a promising candidate important for renewable and environmentally friendly energy source. A major part of the project is educating and training graduate and undergraduate students through interdisciplinary research in advanced organic materials and devices and in materials surface/interface characterization. A strong focus of the program is providing early exposure of research to middle and high school students through programs including University of Rochester Pre-College Experience in Physics for women.