Nanostructured Organic Semiconductors via Directed Supramolecular Assembly

Abstract

Organic small molecule semiconductors have many advantages over their polymer analogues. However, to fabricate organic semiconductor-based devices using solution processing, it is requisite to eliminate dewetting to ensure film uniformity and desirable to assemble nanoscopic features with tailored macroscopic alignment without compromising their electronic properties. To this end, we present a modular supramolecular approach. A quaterthiophene organic semiconductor is attached to the side chains of poly(4-vinylpyridine) via noncovalent hydrogen bonds to form supramolecular assemblies that act as p-type semiconductors in field-effect transistors. In thin films, the quaterthiophenes can be readily assembled into microdomains, tens of nanometers in size, oriented normal to the surface. The supramolecules exhibited the same field-effect mobilities as that of the quaterthiophene alone (10−4 cm2/(V·s)). Since the organic semiconductors can be readily substituted, this modular supramolecular approach is a viable method for the fabrication of functional, nanostructured organic semiconductor films using solution processing.

Nanostructured Donor–Acceptor Self Assembly with Improved Photoconductivity

“…13 Ting Xu and Fréchet et al attached suitably functionalized p-type organic semiconductor -oligothiophene to P4VP resulting in solution processable nanostructured semiconductor composites with charge carrier mobilities comparable to the existing semiconductors already used in OPV devices. 14,15 Both these approaches took aid of the self-assembly afforded by the nanoscale phase separation of the small molecule and preformed polymer. There are several interesting articles in literature whereby the larger length scale phase separation afforded by block copolymers were combined with the small length scale phase separation of small molecules and mesogens to obtain higher degree of organization.…”

Fluidic‐Directed Assembly of Aligned Oligopeptides with π‐Conjugated Cores

“…[8][9][10][11] However, device performance remains hindered in these systems by imprecise morphology. Achieving nano-to mesoscale ordering has become the primary focus of recent efforts, [12][13][14][15][16] wherein π -conjugated structures are constructed by controlling intermolecular orientations via non-covalent π − π , donor/acceptor, and hydrogen bonding interactions, ultimately leading to desired morphology and energy transfer properties. Importantly, these approaches generally lack the absolute control of intermolecular ordering that is imperative for the development of materials with tailored electronic and optoelectronic properties for organic-based devices.…”

Progress in side-chain thiophene-containing polymers: synthesis, properties and applications

“…Alternatively, postfunctionalizing nonconjugated prepolymers with electroactive unites as pendant side chains is a promising strategy to precisely synthesize such electroactive polymer materials for a number of organic electronic applications. Particularly, approaches to post-functionalize flexible polymer backbones with thiophene-based units include weak interaction (e.g., hydrogen bonds [63] and ionic interactions [64]) and covalent bond [26,[65][66][67][68].…”

“…Rancatore et al [63] developed a modular supramolecular approach to fabricating organic semiconductor-based devices using solution processing, which could help overcome dewetting issues to ensure film quality and also induce self-assembled nanoscopic features with tailored macroscopic alignment to maintain their electronic properties. Specifically, a quaterthiophene organic semiconductor is attached to the side chains of poly(4-vinylpyridine) via noncovalent hydrogen bonds ( Figure 2) to form supramolecular assemblies that act as p-type semiconductors in field-effect transistors.…”