A photoswitch based on self-assembled single microwire of a phenyleneethynylene macrocycle

Abstract

Crystalline microwires of a phenyleneethynylene (PE) macrocycle self-assembled from solution exhibited superior photoconductive properties. Photoswitches fabricated with single wires afforded nA-scale photocurrents with on/off ratios of ca. 10(3). At a bias of 30 volts highest gain value achieved was up to 4.5. The stable and rapid responses to light qualify these microwire-based devices for excellent photoswitches or photodetectors.

High Performance Photoswitches Based on Flexible and Amorphous D–A Polymer Nanowires

“…Relative to dark current, the current increased about 2000 times in a short time, and was highly reproducible without obvious attenuation after several cycles of on/off operations. To the best of our knowledge, the obtained switch ratio of 2000 is the highest reported for a conjugated polymer nanowire‐based photoswitch, and is comparable to those of photoswitches based on organic small molecule single crystal nanowires (highest switch ratio = 6000) 8, 10, 28. For comparison, we also fabricated photoswitches based on PFTBT thin films.…”

“…Intensive research has been focused on 1D nanostructures from organic π‐conjugated molecules for their potential application in integrated nano‐ or micro‐optoelectronic devices 1–10. Conjugated polymers are an emerging class of cost‐effective and solution‐processable semiconducting materials with the attractive advantage of mechanical flexibility and the incorporation of functionalities by molecular design 11–16.…”

“…Consequently, nanowires based on conjugated polymers are potential candidates for the achievement of high performance nanoscale photoswitches. However, to date, the switch ratios of conjugated polymer nanowire‐based photoswitches reported in the literature are lower than 10,21, 22 which lags far behind the development of small molecular nanowire‐based photoswitches (switch ratios over 10 3 ) 7–10, 28. Therefore, it is imperative to prepare large‐scale, high‐quality conjugated polymer nanowires with excellent photoswitching properties.…”

Columnar Liquid Crystalline Self‐Assembly of Hydrogen‐Bonded Rod–Coil Diblock Complexes Created from Pyrazole/Benzoic acid Derivatives

“…The formation of a lamellar phase from complex 1 , with a low f coil/rod (0.64), indicates that the alkyl chains are too short to surround the aromatic cores; instead, aromatic tetramers are stacked in parallel, and then the aliphatic chains are interdigitated to yield infinite layers. For complexes 2–4 , with higher f coil/rod (0.91 for 2 , 0.96 for 3 , and 1.37 for 4 ), the columnar phases allow more space for the bulky chains, reducing the repulsive force between aliphatic chains, and enabling adoption of less strained aromatic packing …”

Phenyl–Acetylene Bond Assembly: A Powerful Tool for the Construction of Nanoscale Architectures

“…The Ziessel group reported the same transformation under similar conditions (NaOH in benzene at 70 °C) for 14 h, but only obtained a 45 % yield with the majority of the starting material reisolated,106 indicating the relative difficulty involved in reproducing this statistical deprotection. Luo et al107,108 have recently shown by monitoring the deprotection more closely by TLC that the monodeprotected product can be obtained within 20 min. By dissolving 54 (Scheme ) in toluene in the presence of K 2 CO 3 (4.4 equiv.…”