ABSTRACT
General synthetic methods for silver nanoparticles are reduction of metal salt in aqueous solution or alcoholic solution. However, the preparation of silver nanoparticles in organic solvent is rarely reported. The most common preparation methods for silver nanoparticles in organic solvent are based on transfer of nanoparticles from aqueous phase to organic phase by phase transfer agent. We describe an easy synthetic method to prepare dispersed silver nanoparticles (approximately 10 nm) by reduction of silver cation in organic solvent such as toluene using a reducing agent and a capping agent. The synthesized silver nanoparticles and polycarbonate were mixed and molded to prepare a new composite in methylene chloride. The composite was tested to investigate antifungal effect by coliform (Escherichia coil ATCC 25922). The antifungal effect of the composite reached high after 24 h (99.9999%). The composite and the silver nanoparticles have been characterized using X-ray diffraction (XRD), UV-vis spectroscopy, transmission electron microscopy (TEM), and inductively coupled plasma (ICP).
Subject(s)
Antifungal Agents/chemical synthesis , Metal Nanoparticles/chemistry , Nanotechnology/methods , Polycarboxylate Cement/chemistry , Silver/chemistry , Antifungal Agents/pharmacology , Crystallization , Enterobacteriaceae/metabolism , Escherichia coli/metabolism , Methylene Chloride/chemistry , Microscopy, Electron, Transmission/methods , Nanocomposites/chemistry , Nanostructures/chemistry , Spectrophotometry, Ultraviolet/methods , Surface PropertiesABSTRACT
Nano-sized nickel sulfides were synthesized by the thermolysis of nickel alkanethiolates in the presence of coordinating ligands. Nickel alkanethiolates were synthesized by the reaction of the square planar nickel 1-dimethylamino-2-methyl-2-propanolate [Ni(dmamp)2] with various n-alkanethiols. The effect of ligands in the reaction system has been investigated to control the size and shape of nano-sized nickel sulfides. TEM images show that the products are nano-sized nickel sulfides in rod and plate shapes. Nickel alkanethiolates and nano-sized nickel sulfides have been characterized by means of X-ray diffraction and transmission electron microscopy.
ABSTRACT
A self-catalytic method to selectively grow ZnO nanoneedles is demonstrated by simply combining a conventional micro-contact printing (mu-CP) and two-step metal-organic chemical vapor deposition (MOCVD) techniques. Self-assembled monolayers (SAMs) of octadecyltrichlorosilane (OTS) were patterned on Si substrates by mu-CP. The patterned structures of the ZnO nanoneedles were realized on the SAMs-patterned Si substrates by two-step MOCVD at high temperature of 600 degrees C via the initial preparation of a thin ZnO seed layer with retaining the patterned morphology at low temperature of 170 degrees C. This combined method of mu-CP and self-catalytic two-step MOCVD should be applicable to fabricate the patterned alignments of metal oxide nanostructures.
ABSTRACT
Monodispersed ZnO nanoparticles are easily prepared by the thermolysis of EtZnO(i)Pr as a single molecular precursor and TOPO without any extra solvent as well as any oxygen source.