| As a new type of green environment friendly solvent, room temperature ionic liquid(RTIL) have great advantage over the traditional solvents, such as negligible vapor pressure, low melting points, wide range of liquid temperatures, high polarity, low toxicity, large electrochemical window, high ionic conductively and thermal stability, etc.. So, RTIL have been widely used in the organic chemical reactions, separation, and electrochemical. Presently, RTIL have been widely used in the synthesis of metal nanoparticles, metal-oxide, nano-porous materials, molecular sieve and so on, and provide a new route for the synthesis of nano-materials.In this paper, ZnO nano-materials have been synthesized the ultrasonic or microwave irradiation method in the RTIL [BMIM][PF6]. This method is a rapid, nontoxic and environment friendly synthesis route. CuS and Ag nano-materials have been synthesized via liquid phase method in the ionic liquid ([BMIM][PF6]) aqueous solution. The products were characterized by XRD, EDX, FESEM, TEM, HRTEM, UV-Vis and PL techniques. The main points can be summarized as followed:1. Sonochemistry is a result of acoustic cavitations:the formation, growth, and implosive collapse of bubbles in a liquid. The chemical effects of cavitations are highly dependent on the contents of the collapsing bubble and hence on the choice of solvent. However, the solvent with lower vapor pressure would favor the sonochemical reaction. In this meaning, RTILs are suitable candidates to play such role. So, Rod-like ZnO nanocrystals have been synthesized via an ultrasound-assisted way in the ionic liquid aqueous solution. The as-prepared ZnO nanorods have a diameter of about 50 nm and a length of 1-2μm. A plausible four-step mechanism was proposed to explain the formation of ZnO nanorods. It was found that the lowered ion diffusion velocity in the water-ionic liquid medium could largely contribute to the formation of the ZnO nanorods.2. The microwave-assisted RTILs method is a facile and environment friendly route to the preparation nanostructured materials. Heating by microwave can accelerate the reaction evidently, and the polarization of ions under the rapidly changing electric field of the microwave results in anisotropic growth of crystals. While, the RTILs with the high ionic conductivity and polarizability of cations is an excellent microwave absorbing agent, leading to a high heating rate and a shorten reaction time. By combing the advantages of both RTILs and microwave heating, ZnO nanorods have been successfully synthesized. The results showed that the as-prepared ZnO nanorods have a diameter of about 20 nm and a length of 400～500 nm, and the ionic liquid [BMIM][PF6] played a key role. A plausible three-step mechanism was proposed to explain the formation of ZnO nanorods. This facile and environment friendly synthetic strategy many open new route to the preparation of other ID functional nanomatericals.3. Liquid precipitation method is one of the most popular methods of synthesis nanometer powders. CuS flower-like sphere micro/nanostructure have successfully synthesized via liquid precipitation method by the reaction between CuCl2·2H2O and TAA in the ionic liquid [BMIM][PF6] aqueous solution. The results showed that the as-prepared CuS flower-like sphere have a diameter of about lμm and the ionic liquid [BMIM][PF6] played a key role. UV-Vis curves indicate a single peak centered at 268 nm. PL curves indicated the two peaks centered at 432 nm and 570 nm. The results showed the CuS flower-like sphere micro/nanostructure have a good optical properties.4. The flower-like Ag nanostructure was synthesized via liquid phase reduction method in the presence of silver nitrate, ascorbic acid and citric acid in the ionic liquid [BMIM][PF6] aqueous solution at room temperature. The flower-like Ag nanostructure is composed of nano-petals of the diameter of about 30 nm. The results showed reaction time and IL play important roles in the formation of Ag nanostructure.
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