Fluorescent microspheres of zinc 1,2-dicarbomethoxy-1,2-dithiolate complex decorated with carbon nanotubes

A new discrete bis-dithiolene complex, [PPh4](2)[Zn(DMED)(2)] (1; DMED=1,2-dicarbomethoxy-1,2-dithiolate) with sulfur-based radical character was synthesized and structurally characterized. Complex 1 is stable and exhibits a square planar geometry around the zinc metal. 1 forms nanospheres through a one-pot water-induced self-assembly in a mixture of solvents (acetonitrile-water). These nanospheres were further decorated with water-soluble carbon nanotubes (wsCNTs) through hydrogen bonding between the peripheral -COOCH3 groups of 1 and surfacial carboxyl groups of wsCNTs to assemble into a spherical nanocomposite. The as-prepared nanocomposite showed fluorescence emissions in visible region due to the separation of energy states of the nanospheres assisted by wsCNTs, suggesting the future possibilities of these new materials for use in biomedical application.