Enhanced Photoluminescence of Mesostructured Organosilica Films with a High Density of Fluorescent Chromophores

Abstract

Synthesis of mesostructured materials containing a high density of organic chromophores in the frameworks is highly desired for applications in unique optical devices using energy transfer. However, a dense accumulation of fluorescent chromophores in solid form generally causes concentration quenching. In this study, dense embedding of the chromophore 1,6‐diphenylpyrene within the framework of mesostructured organosilica films results in efficient blue fluorescence emission with high quantum yields of over 0.75. In contrast to conventional fluorescent films where chromophores are diluted and isolated to suppress concentration quenching, increasing the density of 1,6‐diphenylpyrene moieties within the mesostructured framework leads to the efficient formation of highly emissive excimers. Mesostructured frameworks achieving both high light‐absorptivity and efficient fluorescence emission have great potential in light‐emitting materials, fluorescence sensors, and light‐harvesting components for photoluminescent and photocatalytic systems.

A light-switching pyrene probe to detect phase-separated biomolecules

“…Fluorescence emission spectra of Pyr-A comprised two bands near 400 nm and 470 nm, whose intensities varied with solvent type ( Figure 2 C). The shorter- and longer-wavelength bands are similar to those of monomer and excimer emission of other pyrenes except that sharp emission peaks in the monomer band were smeared out by adjacent phenyl rings, as reported previously ( Imai et al., 2012 ; Mizoshita and Inagaki, 2018 ). These assignments were supported by time-resolved fluorescence measurements ( Figure S1 A, Table 1); although the fluorescence lifetime was shorter than that of unmodified pyrenes due to the radiation decay rate enhanced by adjacent phenyl rings, the longer-wavelength emission decayed slowly (tens of nanoseconds), whereas the shorter-wavelength emission decayed rapidly (within several nanoseconds), consistent with the long-lived nature of pyrene excimers ( Weltman et al., 1973 ).…”

Non-K Region Disubstituted Pyrenes (1,3-, 1,6- and 1,8-) by (Hetero)Aryl Groups—Review

“…Investigation of the efficient organic light-emitting devices based on pyrene derivatives was also a stimulus to the synthesis of 1,6-disubstituted pyrenes, which contain various aryl groups 20 – 28 , such as presented in Scheme 12, Scheme 13, Scheme 14 and Scheme 15 [4,8,47,48,49,50]. All reactions used [Pd(PPh 3 ) 4 ] as a catalyst and are divided in reference to applied bases Na 2 CO 3 , NaOH, and K 2 CO 3 , and solvents PhMe/EtOH, 1,4-dioxane, and THF.…”

“…Disubstituted pyrenes of this type are interesting in themselves and can act as substrates in the synthesis of the other molecules that also exhibit expected properties. The vast majority of disubstituted pyrenes can be applied in organic electronics in materials such as organic light-emitting diodes (OLEDs) [4,5,6,7,8,9], organic field-effect transistors (OFETs) [10,11], and solar cells [12] but also in the synthesis of nanographenes [13], metal cages [14,15], and many others. A wide spectrum of methods for the synthesis of the reported compounds exists, though a fundamental problem lies within the methods’ ordering.…”

Highly selective fluorescence detection of Cu2+ based on Schiff base functionalized periodic mesoporous organosilicas

“…The SCN-PMO solid sensor exhibited excellent recyclability and regeneration. [20] Furthermore, results of the Cu 2+ ion detection experiment for SCN-PMO in zebrafish showed its great potential for use in biotechnological and biomedical applications.…”