Rapid formation and real-time observation of micron-sized conjugated nanofibers with tunable lengths and widths in 20 minutes by living crystallization-driven self-assembly.

Sanghee Yang,Tae-Lim Choi

doi:10.1039/d0sc02891f

Sanghee Yang, Tae-Lim Choi

Open Access

https://doi.org/10.1039/d0sc02891f

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Abstract

Preparing well-defined semiconducting nanostructures from conjugated polymers is of paramount interest for organic optoelectronic devices. Several studies have demonstrated excellent structural and size control from block copolymers (BCPs) containing non-conjugated blocks via crystallization-driven self-assembly (CDSA); however, the precise control of their size and shape remains a challenge due to their poor solubility, causing rapid and uncontrolled aggregation. This study presents a new type of fully conjugated BCP comprising two polyacetylene derivatives termed poly(cyclopentenylene-vinylene) to prepare semiconducting 1D nanofibers. Interestingly, the widths of nanofibers were tuned from 12 to 32 nm based on the contour lengths of their crystalline core blocks. Their lengths could also be controlled from 48 nm to 4.7 μm using the living CDSA. Monitoring of the growth kinetics of the living CDSA revealed the formation of micron-sized 1D nanofibers in less than 20 min. The rapid CDSA enabled us to watch real-time growth using confocal fluorescence microscopy.

Highlights

Conductive molecules are highly advantageous for sensors, functional coatings, and electronic devices.[1,2,3,4] Among them, conjugated polymers have gained enormous attention due to their advantageous physical properties including their low weight and exibility.[5,6,7] For example, poly(3-hexylthiophene) (P3HT),[8,9,10] poly(para-phenylenevinylene) (PPV),[11] and poly uorene (PF)[12] have been widely used in various device applications
For the spontaneous formation of the conjugated nanoparticles, we have developed another strategy termed In situ Nanoparticlization of Conjugated Polymers (INCP).[38,39,40,41,42]
We report the formation of well-de ned semiconducting 1D nano bers from block copolymers (BCPs) having the PCPV as the core block and another PCPV as

Summary

Introduction

Conductive molecules are highly advantageous for sensors, functional coatings, and electronic devices.[1,2,3,4] Among them, conjugated polymers have gained enormous attention due to their advantageous physical properties including their low weight and exibility.[5,6,7] For example, poly(3-hexylthiophene) (P3HT),[8,9,10] poly(para-phenylenevinylene) (PPV),[11] and poly uorene (PF)[12] have been widely used in various device applications. As the width of the 1D nano bers could be precisely controlled, we attempted to control their lengths by using the living CDSA; epitaxial growth from the uniform seed through the addition of unimers.

Results

Conclusion