A ruthenium bipyridyl-dye sensitizer (N) based on the naphthyl-thiazole anchoring-ancillary ligand was synthesized and characterized using spectroscopic methods of UV-Vis, 1 H NMR, FTIR and fluorescence. The functional properties of N were investigated through its photoinduced and intramolecular based charge transfer mechanisms. Subsequently, N displayed interesting charge transfer-based properties (ESIPT) that are complementary to molecular photovoltaic and chemosensing properties. The properties were investigated and studied in dimethyl sulfoxide (DMSO), due to its polar nature and solubility of the dye. Dye sensitizer exhibitions were investigated through solvatochromism effect on the optoelectronic properties, while chemosensing abilities were inspected through colorimetric activities, upon molar addition of anions. Thus, it was established that a dual functional N is a potential dye sensitizer with optoelectronic properties displaying high molar extinction coefficients in acetone. In addition, it was found that N is a colorimetric and fluorometric probe selective and sensitive to biologically important anions of CN − , F − , OH − and AcO − through fluorescence enhancement, as a result of hydrogenbonding leading to deprotonation. The sensing probe, however, displayed more strongly association with CN − .

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A ditopic multi-colorimetric probe based on the phenylpridyl-thioic moiety (EN) was synthesized via a Schiff base reaction mechanism and characterized using 1H NMR and UV-vis spectroscopy.

Dye sensitizers are entities designed primarily to serve the function of harvesting light photons in the functional wavelength, which is centered on charge transfer mechanisms. A metal-free dye sensitizer (J)...

The field of chemosensing has been experiencing an exponential expansion in recent times, due to increased demands for simpler and user-friendly analytical techniques, in order to combat and confront the challenges of industrial pollutions in the 21 st century. Metal complex-based chemosensors have received little attention while exhibiting excellent sensing properties, comparing to their organic counterparts. Thus, a thiosemicarbazone-based ( H ) and its cadmium complex ( P ) were synthesized, characterized and their photophysical and chemosensing properties were investigated in DMF solvent. The addition of molar equivalents of selected cations (of nitrates or chloride salts) to H and P , produced visually detectable colour changes as well as remarkable spectral shifts. Explicitly, the two probes ( H and P ) were able to collectively discriminate heavy metal cations such as Cd 2+ , Co 2+ , Zn 2+ , Cu 2+ , Ni 2+, and Ag + , both in DMF, among all other heavy metal cations tested. None of the anions could be detected by H or P , even when the tetrabutylammonium salts (TBAs) were used, the action presumably ascribed to the solvent effect. Thus, H and P can be used to selectively and sensitively detect the presence of heavy metal cations, via naked-eye detectable colour changes in an aqueous soluble solvent such as DMF.