Haiqiang Wu

A Novel Chemosensor Based on Rhodamine Derivative for Colorimetric and Fluorometric Detection of Cu2+ in Aqueous Solution

A new rhodamine-based reversible chemosensor (2) was synthesized, which exhibits high sensitivity and selectivity for Cu2+ but no significant response toward other competitive metal ions in aqueous solution. Upon the addition of Cu2+, the spirolactam ring of 2 was opened and the solution color changed from colorless to red. Strangely, an unexpected fluorescence quenching was observed, which is contrary to the fluorescence turn-on of the most rhodamine-based chemosensors. The likely novel sensing mechanism has been proposed.

Preparation and Properties of Aqueous SCNTs Dispersion based on A UV-curable Polymeric Dispersant

A novel photosensitive copolymer P(SS-co-AA-g-GMA) (PSAG) was synthesized and utilized to noncovalently functionalize pristine single-walled carbon nanotubes (SCNTs). PSAG was highly effective for the solubilization of SCNTs in water and validated by UV-vis absorption spectra experiments, resulting in homogeneous and stable PSAG-SCNT aqueous dispersion. The microstructure of SCNTs was observed through Raman spectroscopy and transmission electron microscopy. In addition, compared with the two common polymeric dispersants of Triton X-100 and PSS, PSAG demonstrated more effective performances for dispersing SCNTs under identical conditions. Furthermore, the photosensitive PSAG-SCNTs can be crosslinked after UV irradiation, leading to significant improvement in the water resistance of SCNT films. UV-cured films can be transferred to plastic wrap to form a flexible film with high electrical conductivity.