Synthesis And Characterization Of Nanomaterials In Ionic Liquids

With growing concern over the environmental impact and health hazards oftraditional volatile organic solvents, researchers continue to search for greeneralternatives. Room-temperature ionic liquids (RTILs), are simply liquids that arecomposed entirely of ions with a melting point below 100°C, have been shown tobe viable substitutes for organic solvents both in academia and industry due totheir negligible vapor pressure, low melting points, wide range of liquidustemperatures (up to 400℃), low toxicity, nonflammability, large electrochemicalwindow, good solvents for many organic and inorganic materials, and high ionicconductively and thermal stability, are widely application in the organic chemicalreactions, separations, and electrochemical. In contrast to their successfulapplications in organic and materials chemistry, the use of RTILs in nanostructressynthesis is still in its infancy. In this paper, we synthesized five different RTILs, and then used the RTILs tosynthesize various nanomaterials. By combining the advantages of both RTILs andmicrowave heating, we report a fast, seedless, template-free and environmentallybenign green route for the production of vairous morphological nanostructures bymicrowave-assisted heating in RTILs. The RTILs consists of cation and anion. Thehigh ionic conductivity and polarizability of cation make it an excellentmicrowave absorbing agent, thus leading to a high heating rate and a significantlyshorten reaction time. The movement and polarization of ions under the rapidlychanging electric field of the microwave result in transient, anisotropicmicro-domains for the reaction system, facilitating the anisotropic growth ofvarious nanostructures. We synthesized various morphologies of ZnO, SnO2 andsulfide, etc. by this method. The products were characterized by XRD, SEM, TEM,PL, and we investigated the morphology variations of nanostructures withdifferent conditions. In additional, we synthesized mesostructured SiO2 and TiO2using sol-gel method in different RTILs and dicussed the possible formationmechanism.