• cross-linking
• ETL
• HTL
• OLED
• polymer

This thesis is part of a research activity carried out at King Abdullah University of Science and Technology, more precisely in the Solar Center Department, that draws together experts in materials science, chemistry and physics to explore innovative solutions for solar energy harvesting and conversion.
In this thesis we focus on the synthesis of new cross-linkable organic materials that can be used in electronic devices, such as Organic Light Emitting Diodes (OLEDs).
OLEDs are a nearly new multi-disciplinary research area and the last decades research interest in this field has increased exponentially, due to their commercial potential as market leaders in display technology and ambient lighting solutions.
Despite intense research efforts during the last decade, improvements have still to be made in OLED manufacturing, especially within the deposition of the layers.
Devices can be constructed substantially with two different methodologies: vacuum sublimation or from solutions.
We decided to focus our work on the solution method and since we are considering multi-layer devices, the main challenge in this research field is represented by the dissolution of the previously deposited layers due the solvent used to deposit the subsequent layer(s). This could be tackled by synthesizing cross-linkable organic materials.
Consequently, we designed four new molecules that could be used in OLED devices as electron transport layer (ETL) and hole transport layer (HTL), which incorporate cross-linkable moieties. More precisely the ETL contains a diphenylphosphine oxide-4-(triphenylsilyl)phenyl (TSPO1) central unit, commonly known as a great electron transport material, meanwhile two HTL are based on the 9-(4-(10-phenylanthracene- 9-yl)phenyl)-9H-carbazole (PhPC) and the last one on 4,4'-(anthracene-9,10-diyl)bis(N,N-diphenylaniline) core, which own great hole transport proprieties.
Going ahead, vinylphenyl units have been used to allow the cross-linking of the molecules, through the thiol-ene chemistry, and then to create the insoluble layer. The majority of the synthesis have been made using the Suzuki coupling, which enable us to yield from great to excellent results.
Thus, we have successfully synthesized the molecules that we designed and we confirmed their ability to crosslink as we hypothesized, making those molecules interesting for future application.