Molecules and atoms at material interfaces have properties that are distinct from those found in the bulk. Distinguishing the interfacial species from the bulk species is the inherent difficulty of interfacial analysis. For organic photovoltaic devices, the interface between the donor and acceptor materials is the location for exciton dissociation. Dissociation is thought to occur via a complex route effected by microstructure and the electronic energy levels. The scale of these devices and the soft nature of these materials create an additional level of difficulty for identification and analysis at these interfaces. The transmission electron microscope (TEM) and the spectroscopic techniques it incorporates can allow the properties of the donor-acceptor interfaces to be revealed. Cross-sectional sample preparation, using modern focused ion beam instruments, enables these buried interfaces to be uncovered with minimal damage for high resolution analysis. This powerful instrument combination has the ability to draw conclusions about interface morphology, structure and electronic properties of organic donor-acceptor interfaces at the molecular scale. Recent publications have demonstrated these abilities, and this article aims to summarise some of that work and provide scope for the future.

在材料界面处的分子和原子具有不同于本体中发现的特性。区分界面物种与散装物种是界面分析的固有困难。对于有机光伏器件，施主和受主材料之间的界面是激子离解的位置。认为解离是通过受微观结构和电子能级影响的复杂路线。这些设备的规模和这些材料的柔软特性为在这些界面进行识别和分析带来了额外的难度。透射电子显微镜（TEM）及其结合的光谱技术可以揭示供体-受体界面的性质。使用现代聚焦离子束仪器进行横截面样品制备，可以发现这些掩埋的界面，而对高分辨率分析的损害最小。这种强大的仪器组合能够在分子规模上得出有关有机供体-受体界面的界面形态，结构和电子性质的结论。最近的出版物已经证明了这些功能，