Before society can benefit from the diverse applications of organic electronics, first researchers must improve tunability and reproducibility of organic semiconducting materials and devices. The implementation of organic nanoparticles has improved consistency via increased predictability of heterojunction between n-type and p-type nanoparticles, which pack predictably due to their controlled shape—round, oblong, or cubic, for example. This improvement falls in the realm of the mesoscale—100 nm to 100 µm. Little remains understood, however, about self-assembly on the nanoscale (&lt;100 nm). That is: there is little understanding of the alignment of semiconducting molecules <i>within</i> these nanoparticles. This nanoscale organization affects the optoelectronic properties of the material. Understanding the phenomenon of aggregation is therefore important to achieve tunability, and ultimately highly tailored devices. This study focuses on the role of surfactant in self-assembly. Surfactants are used to achieve femtoliter droplets of dye solutions, which crystallize into nanoparticles upon heating and boiling of the solvent within the droplet. This yields a water suspension of surfactant-decorated solid dye nanoparticles. The goal of this work is to achieve selectivity in H- versus J-aggregation (determined by the alignment of dye molecules), as well as nanoparticle morphology such as spheres versus nanowires. Materials are characterized using UV-Vis and photoluminescence spectroscopies and conductivity measurements to determine optoelectronic properties. Powder X-Ray Diffraction is also used to probe orientation and aggregation type within the crystal.

Tunability in organic electronics: Determination of surfactant role in directed self-assembly

255th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.