Synthesis Of Nickel Bis(Dithiolene) Complexes And Study On Their Property

As a result of unique optical property and physical properties, rare-earth doped upconversion luminescent materials is widely used in infrared quantum counter, temperature inductor and solid-state laser,et al. Especially in recent years, the application in biological optical markers, has attracted widespread interest. Because of low luminous efficiency, the applicaiton of rare-earth doped upconversion luminescent materials is limited. Yb3+is always used as sensitizer to Improve the luminous intensity of upconversion luminescent materials. There is a optimum value for the concentration of Yb3+in the application of upconversion luminescent materials, so it can not increase the concentration of Yb3+indefinitely.Therefore, the study of this article is to synthesis of nickel bis(dithiolene) complexes and prepare for the application in the rare-earth doped upconversion luminescent materials.Three kinds of nickel bis(dithiolene)complexes with different groups were designed and synthesized. These dyes were characterized by mass spectrometry (MS), proton nuclear magnetic resonance spectrometry(1H-NMR) and infrared spectroscopy. The physical and chemical properties were systematically investigated, including photostability, solubility and solvent effect, etc. The results revealed the good thermal stability of the complexes. Strong and broad absorptions in the NIR region (850-970nm) with high molar extinction coefficients of the complexes were observed. With the increasement of solvent polarity, the maximum absorption wavelength of dyes shifts to red in the solvent. With the electron-donating group, the maximum absorption wavelength of dyes shifts to red in the same solvent. In general, it is proved that three kinds of nickel bis(dithiolene)complexes with different groups possess better absorption performance in the NIR region and they can transfer energy to rare-earth doped upconversion luminescent materials in theory.