SYNTHESIS AND CHARACTERIZATION OF PERYLENE DIIMIDE DERIVATIVES FOR THE PREPARATION OF ORGANIC SEMICONDUCTORS THROUGH THE PRECURSOR APPROACH

Work package:
Organic electronic materials present a characteristic flat structure involving several polyaromatic connections that endow these molecules with enough charge mobility to work as semiconductors, when deposited in form of thin-films of just few nanometers thick. However, the desired planarity hampers the solubility of these compounds, thus posing big challenges in the films' preparation during the device manufacture. In order to favour the greener solution processing techniques, the precursor approach appears as a young promising strategy based on the preparation of a molecular soluble precursor that can be easily deposited on top of a substrate. Thereafter, it can be transformed in the desired organic semiconductor via post-deposition treatment, such as thermal stimuli or light irradiation (Figure 1a).1 Owing to the scarce number of examples, the project herein seeks to develop new photochemical strategies for the transformation of precursors in the desired functional materials. To do so, we will pursue the synthesis of new compounds deriving from perylene diimide (PDI), an intense red dye with proved applications in photovoltaics, transistors and OLEDs.2 The precursors will include a singular 3D scaffold that, under a specific light source, will be planarized rendering the desired electronic material (Figure 1b). Thus, this master internship will involve multi-step organic synthesis of PDI derivatives as soluble precursors, characterization of the resulting organic materials and investigation of solid-state transformations to yield the target semiconductors. The student will be trained, as well, in thin-film processing techniques to identify promising materials.