Textile Display for Electronic and Brain-Interfaced Communications.

Textile displays are poised to revolutionize current electronic devices, and reshape the future of electronics and related fields such as biomedicine and soft robotics. However, they remain unavailable due to the difficulty of directly constructing electroluminescent devices onto the textile-like substrate to really display desired programmable patterns. Here, a novel textile display is developed from continuous electroluminescent fibers made by a one-step extrusion process. The resulting displaying textile is flexible, stretchable, three-dimensionally twistable, conformable to arbitrarily curved skins, and breathable, and can dynamically display a series of desired patterns, making it useful for bioinspired electronics, soft robotics, and electroluminescent skins, among other applications. It is demonstrated that these displaying textiles can also communicate with a computer and mouse brain for smart display and camouflage applications. This work may open up a new direction for the integration of wearable electroluminescent devices with the human body, providing new and promising communication platforms.

Importance of C(2) symmetry for the device performance of a newly synthesized family of fused-ring thiophenes.

We investigated the relationship between molecular structure and field-effect hole mobility in a family of fused-ring polythiophene copolymers that we designed recently. The results suggest that a repeat unit that possesses a C(2) axis perpendicular to the conjugation plane is important to achieve a high-mobility. Our finding is supported by a review of literature data: Many polymer semiconductors showing a hole or electron mobility >0.1 cm(2)/V.s feature a repeat unit with C(2) symmetry; however exceptions have been found from some push - pull polymer structures.

Alkylsubstituted thienothiophene semiconducting materials: structure-property relationships.

A family of conjugated polymers with fused structures consisting of three to five thiophene rings and with the same alkyl side chains has been synthesized as a means to understand structure-property relationships. All three polymers showed well-extended conjugation through the polymer backbone. Ionization potentials (IP) ranged from 5.15 to 5.21 eV; these large values are indicative of their excellent oxidative stability. X-ray diffraction and AFM studies suggest that the polymer with the even number of fused thiophene rings forms a tight crystalline structure due to its tilted side chain arrangement. On the other hand, the polymers with the odd number of fused thiophene rings packed more loosely. Characterization in a field-effect transistor configuration showed that the mobility of the polymer with the even number of rings is 1 order of magnitude higher than its odd-numbered counterparts. Through this structure-property study, we demonstrate that proper design of the molecules and properly arranged side chain positions on the polymer backbone can greatly enhance polymer electronic properties.

Tetrathienoacene copolymers as high mobility, soluble organic semiconductors.

Increasing the rigidity of the thiophene monomer through the use of an alkyl-substituted core that consists of four fused thiophene rings is shown to be a promising route toward high-performance organic semiconductors. We report on a dialkylated tetrathienoacene copolymer that can be deposited from solution to yield ordered films with a short pi-pi distance of 3.76 A and with a field-effect hole mobility that exceeds 0.3 cm2/V.s. This polymer enables simple transistor fabrication at relatively low temperatures, which is particularly important for the realization of large-area, mechanically flexible electronics.

Acid-sensitive semiperfluoroalkyl resorcinarene: an imaging material for organic electronics.

An acid-sensitive semiperfluoroalkyl resorcinarene was synthesized, and its lithographic properties were evaluated. Its solubility in segregated hydrofluoroether solvents enables the patterning of delicate organic electronic materials.