Abstract:
Micro/nano copper powders were synthesized by an ionothermal method using Cu(NO
3)
2 as the copper source, hydrazine hydrate as reducing agent, and different kinds of ionic liquids as reaction medium, under the different reaction temperature.The influence of the type of the reaction medium and the pH value of the solution on the morphology of micro/nano copper particles were studied.The prepared samples were characterized by XRD, SEM, XPS and ultraviolet-visible (UV-vis) spectrum, respectively.XRD results indicated that when the reaction temperature was between 120℃ and 160℃, the prepared sample was only copper phase, and the sample prepared by the reaction temperature reached 180℃, and the Cu
2O was formed.SEM results indicated that when the reaction medium is tetraethyl ammonium bromide/butanedioic acid ionic liquid system, the prepared micro/nano copper crystals are triangular, and the micro/nano copper crystals prepared in the urea/choline chloride reaction medium is not regular sphere.The UV-vis spectrum result indicated that in the wavelength range of 200~900 nm, the triangle-like copper micro/nano crystals exhibited two absorption peaks centered at 525 nm and 605nm, respectively.The triangle-like copper micro/nano crystals will be applied in surface enhanced spectroscopy and plasmonics field.