Modulating electrophoretic deposition behavior of P3HT via solution-based morphological control

• Published in: Journal of materials research Vol. 40; no. 12; pp. 1864 - 1876
• Main Authors: Kreis, Nicholas, Mo, Sixing, Ma, Guorong, Guo, Song
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 28.06.2025; Springer Nature B.V
• Subjects: Applied and Technical Physics; Biomaterials; Chemistry and Materials Science; Dielectrophoresis; Doping; Electric fields; Electrodes; Electrophoretic deposition; Inorganic Chemistry; Materials Engineering; Materials Science; Microfibers; Nanoparticles; Nanotechnology; Nanowires; Optoelectronics; Substrates; Electrodeposition; Polymer; Patterning; Self-assembly
• ISSN: 0884-2914; 2044-5326
• DOI: 10.1557/s43578-025-01618-3

The electrophoretic and dielectrophoretic deposition behavior of poly(3-hexylthiophene) (P3HT) nanowires (NWs) and nanoparticles (NPs), using the same electric field setup was investigated. When applying a 60 V bias to an interdigitated electrode (IDE) substrate, P3HT NWs deposit directly onto the negatively charged electrodes, while P3HT NPs form microfibers between oppositely charged electrodes (200 µm) in non-polar solvents. P3HT NW aggregates, due to their surface area and charge accumulation, undergo electrophoretic deposition (EPD). Whereas the P3HT NPs, with their larger size and reduced charge separation, form microfibers via dielectrophoretic (DEP) assembly. Potential sources for NWs’ positive charge are discussed. In addition, electrochemical doping was explored as a post-deposition treatment to modify the optoelectronic properties of the films, demonstrating a significant fluorescence quenching upon doping. This work shows that manipulating the nanoaggregate structure leads to differing deposition behavior, offering a pathway for more controlled and scalable fabrication of conjugated polymer (CP)-based devices. Graphical abstract