Cross-Linking Silsesquioxane Cages with Polyaromatics as Fluorescent Porous Polymers for Fluoride Sensing and Removal

Abstract

Fluorescent polymer nanocomposites of silsesquioxane cage-based anthracene (An-PSQ) and pyrene (Py-PSQ) were obtained by cross-linked polymerization of octavinylsilsesquioxane (OVS) with 9,10-dibromoanthracene or 1,6-dibromopyrene, respectively. The fluorescent polymers are insoluble and were structurally characterized by FT-IR and NMR. Polyaromatic spacer groups incorporated into materials could tune and rigidify in both micro-and mesoporous structures with high surface area in comparison to silica-based materials in the range of 246−342 m 2 / g, and their XRD analyses also show the amorphous nature. Both An-PSQ and Py-PSQ exhibit solvent-polarity-dependent photophysical properties in both light absorption and emission, which were employed in the anion sensing (i.e., F − , CN − ) in high polarity organic media. Importantly, excimer natures of polyaromatic spacer groups among silsesquioxane cages play an important role in the selectivity of anions in recognition. An-PSQ gives spectral changes in the presence of both F − and CN − , whereas replacing anthracenyl to pyrenyl group in Py-PSQ could selectively detect only F − because of a stronger excimer feature. Moreover, strong fluoride−silsesquioxane interaction has provided another function to these materials as adsorbent for highly hydrophilic F − anion from organic media containing water up to 77%.

Silsesquioxane-based and triptycene-linked nanoporous polymers (STNPs) with a high surface area for CO2 uptake and efficient dye removal applications

“…[19][20][21][22] OVS derived porous materials may also be promising materials for lightharvesting applications, 23 catalysis, photo-voltaic or electronic devices, 24,25 and sensors for explosive detection. [26][27][28] Such silsesquioxane based hybrid porous materials can be conveniently synthesized using various synthetic strategies that include (but are not limited to) the Friedel-Crafts reaction, 26,29 hydrosilylation, 30 and coupling reactions such as the Heck reaction, 17,31 Sonogashira 32 and Yamamoto. 33 While most coupling reactions employ expensive transition metal catalysts and rigorous reaction conditions, the use of Friedel-Crafts reaction conditions makes the polymerization facile, economical as well as versatile.…”

Enhanced Electrochemical Properties of Catalyst by Phosphorous Addition for Direct Urea Fuel Cell

“…65-2865, Ni (Nickel)]. The catalyst can be checked for detailed surface properties through XPS characterization by further analysis (Wannasiri et al, 2020). This allows the monomeric metal catalysts of Ni and Pd formed at MWCNTs to be more dispersed over the catalytic support and thus identify the peak of the Ni-Pd catalytic structure, 41.0 • , which is combined in a hetero-dispersive system (Yan et al, 2012;Liu et al, 2017).…”

Design of Fluorescent Hybrid Materials Based on POSS for Sensing Applications

“…The response time of the PySQ selective capture of fluoride ions was less than 2 min with the detection limit of 0.00161 μM. Recently, another POSS-based fluorescent porous polymer was reported for fluoride sensing and removal by a similar mechanism, in which anthracene and pyrene were used as polyaromatic spacer groups [ 99 ]. In 2019, Tang and coworkers reported a ratiometric fluorescence sensor based on octa-pyrene-modified POSS organic framework nanoparticles for the detection of F¯ ( Figure 20 a) [ 100 ].…”