π-Conjugated nanostructured materials: preparation, properties and photonic applications

Abstract

The preparation, properties, and photonic applications of π-conjugated nanostructured-materials are reviewed.

Development of a near infrared novel bioimaging agent via co-oligomerization of Congo red with aniline and o-phenylenediamine: experimental and theoretical studies

“…[14][15][16] Several investigations have been reported on the design of donor-acceptor based conjugated polymers for their potential application in bio-imaging and photodynamic therapy. [17][18][19][20] However, scant literature is available on the design of conjugated polymers through the insertion of azo dyes in the main chain via co-oligomerization/doping. 21,22 Azo compounds are extensively used in optical storage, 23 optical switching, 24 non-linear optical devices 25 as well as various kinds of photonic devices.…”

Different PEG‐PLGA Matrices Influence In Vivo Optical/Photoacoustic Imaging Performance and Biodistribution of NIR‐Emitting π‐Conjugated Polymer Contrast Agents

“…[ 2 ] It is known that the processing of fluorophores into nanoparticle formulations can greatly change their optical properties compared to the solution form. [ 16 ] Normalized absorption and emission spectra of PCPDTBT in THF and CPN formulations ( Figure A) clearly show this effect. Due to the reduction in the conjugation length through bending, torsion and kinking, nanoparticulate PCPDTBT shows a blue shift (≈20–50 nm) of the absorption maximum [ 54 ] and a general broadening of the absorption spectrum [ 55,56 ] compared to PCPDTBT dissolved in THF.…”

“…The CPN formulations also show a large red shift in the emission maxima (≈80 nm) compared to the THF solution, which is also due to spatial changes in the polymer structure caused by increased formation of interchain aggregates and increases pi‐pi interactions as a result of increased interchain interaction in the solid state. [ 16,57–59 ] PLQY (photoluminescence quantum yield) values (Figure 1B) of CPN were 10–50 fold lower than PCPDTBT dissolved in THF, and despite an identical redshift of the emission spectra PEG‐PLGA PLQY values were three‐ to fivefold lower than the core–shell PEG 2kDa ‐DPPE formulation. Overall, the measured PLQY values correspond to literature values: PCPDTBT dissolved in toluene (0.5%), in chloroform (0.4%), [ 31 ] and in nanoparticle formulations (0.1–2.5%) [ 31,60,61 ] have been reported.…”

Solution Processable Transition Metal Phthalocyanine Nanofibres

“…This has resulted in the development of a fully solution processable OLEDs from solution processed anodes, cathodes and light emitting layers . Further, nanoarchitectures of organic materials offer additional opportunities to conventional materials for diverse applications, including solid‐state lighting, solid‐state lasers, biophotonics, photodynamic therapy, etc . Nanostructures of MPcs may possess competitive properties such as good dispersibility, high surface area, high reactivity and flexibility .…”

“…[16] Further, nanoarchitectures of organic materials offer additional opportunities to conventional materials for diverse applications, including solid-state lighting, solid-state lasers, biophotonics, photodynamic therapy, etc. [17] Nanostructures of MPcs may possess competitive properties such as good dispersibility, high surface area, high reactivity and flexibility. [18] Many known synthetic procedures to prepare MPc nanostructures are based on topdown approaches and self-assembly.…”