Synthesis, properties, and electronic applications of size-controlled poly(3-hexylthiophene) nanoparticles

Semiconducting polymer nanoparticles have attracted increasing interest for the facile fabrication of organic electronic devices. These nanoparticles could provide the ability to control thin film morphology independently of optical and electronic properties. Using poly(3-hexylthiophene), we demonstrate surfactant-free synthesis and characterization of size-controlled, semicrystalline polymer nanoparticles. Our method produces discrete nanoparticles that can be deposited from solution into thin films. By controlling the molecular weight, polydispersity, and regioregularity of the polymer as well as varying its initial solution concentration, we tune both the size and crystallinity of the resulting nanoparticles. Organic field effect transistors (OFETs) using nanoparticles made from this method produce good semiconducting devices with hole mobilities on the order of 10^-3 cm²/(V s). This approach to forming polymer nanoparticles is attractive for the introduction of solution-processable, well-characterized nanoscale crystalline domains of a variety of conjugated polymers and should be useful for the fabrication and optimization of organic electronic devices.