Effects of Sonication and Hydrothermal Treatments on the Optical and Chemical Properties of Carbon Dots.

In our study, we have tested the effects of sonication and hydrothermal treatments on the properties of carbon dots synthesized from a microwave-assisted method (C-dots). When the carbon dots are sonicated in an aerobic environment, the fluorescence quantum yield decreases drastically because the molecular fluorophores attached to the surface of the carbon dots are oxidized during the sonication process. Meanwhile, the sonicated C-dots also lose their Hg ion sensing and photoreduction activity due to the oxidization of surface functional groups.

Intra- and intermolecular hydrogen bonds enhance the fluoride-responsiveness of functionalized glycolipid-based gelators.

We propose a facile approach toward enhancing the efficiency of fluoride-responsive gels through the positioning of functionalized receptor units, allowing tunable intra- and intermolecular hydrogen bonding, in the gelator molecules. We prepared the new glycolipid-based gelator 2 and its hydroxy and methoxy derivatives 2a and 2b, respectively, to study the effects of three types modes of supramolecular assembly: solely intermolecular hydrogen bonding in 2, solely intramolecular hydrogen bonding in 2b, and both inter- and intramolecular hydrogen bonding in 2a. H NMR spectra confirmed the self-assembly interactions of these glycolipid-based gelators.