Microwave-assisted synthesis and characterization of CuO nanocrystals

CuO feather-like and flower-like crystals have been synthesized by a fast microwave-assisted solution approach using Cu(NO3)(2) and NaOH. The morphology transformation of CuO could be achieved by ionic liquid 1-n-butyl-3-methyl imidazollium tetrafluoroborate ([BMIIM]BF4)With [BMIM]BF4, flower-like CuO were obtained, whereas without [BMIM]BF4, featherlike CuO were obtained. The possible formation mechanism of flower-like CuO was discussed on the basis of experimental results. The products were characterized by XRD, FESEM/EDS, and TEM/SAED. In addition, the adsorption of [BMIM]BF4 on flower-like CuO was confirmed by FTIR and TG/DSC, and the band gap energies of the flower-like CuO was estimated by UV-vis spectra.