An efficient room-temperature route to uniform ZnO nanorods with an ionic liquid

Rod-like ZnO nanocrystals have been synthesized via an ultrasound-assisted way by the reaction between Zn(CH3COO)2·2H2O and NaOH in the ionic liquid 1-butyl-3-methyl imidazole six hexafluorophosphoric acid salts ([BMIM][PF6]) aqueous solution. The products were characterized by XRD, EDX, FESEM, TEM, HRTEM, UV–Vis and PL techniques. The as-prepared ZnO nanorods have a diameter of about 50 nm and a length of 1–2 μm. 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. The effects of experimental parameters on the formation of the products were also explored.