Lithium ion as growth-controlling agent of ZnO nanoparticles prepared by organometallic synthesis

Abstract

OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible. This is an author-deposited version published in: http://oatao. (series 3) were used. Interestingly, Li precursors induce a modification of the growth of the particles while, no effect is observed when Na precursors is used. Indeed, isotropic nanoparticles were obtained when Li precursors were used while nanorods were formed with Na precursor as already observed in the same experimental conditions without alkali-metal precursor.Observations by TEM show that as the Li/Zn molar ratio increases, the mean diameters of the nanoparticles vary from 3.7 AE 0.7 nm to 2.5 AE 0.4 nm, and from 4.3 AE 1.0 nm to 3.1 AE 0.8 nm for series 1 and series 2, respectively, while the length and the diameter of the nanorods are ca. 11 Â 4 nm, for series 3. Interestingly, the consequence of the lithium induced size variation leads to a shift of the emission band in the visible range, from yellow to blue through white as a function of increasing concentration of lithium precursor. The intensity of this emission is strong enough to be clearly seen by the human eye.

Hydrolysis of organometallic and metal–amide precursors: synthesis routes to oxo-bridged heterometallic complexes, metal-oxo clusters and metal oxide nanoparticles

“…65,66 Upon hydrolysis, metal-amide reagents form amines that may remain coordinated to the metal as a neutral Lewis basic ligand, although volatile amines such as NMe2H can be removed in vacuo. 67 The hydrolysis of organometallic species can offer an additional benefit, as the alkane or arene by-products are essentially inert and have a negligible effect upon the surface chemistry of the resultant metal-oxo nanostructures. This contrasts with the synthesis of metal-oxo species from the reaction of metal halides with water or alcohols, where the halide may be incorporated into the reaction product.…”

“…Chaudret, Kahn, and co-workers utilised group 1 metalamides as growth-controlling agents in the hydrolysis of ZnCy2 with octylamine. 67 Without dopant, this route produced ZnO nanorods. However, the addition of Li-amides led to small spherical (wurzite) NPs which became smaller with increasing Li content (1-10% doping was tested, with a size decrease of up to 30% observed).…”

“…As the covalent radii of Li is similar in size to Zn (Li, 1.23 Å; Zn, 1.25 Å), the authors propose that LiOH condenses onto the surface of growing ZnO NPs, hindering further growth and forming a Li rich surface layer. 67 This results in a blue shift of the luminescence of the doped NPs. More recently, Polarz and co-workers prepared highly crystalline Li doped ZnO nanorods by using an oil in water emulsion technique, in which the Zn precursor is added to the oil phase with Li salts dissolved in the aqueous phase.…”

Aminolysis of polyethylene terephthalate surface along with in situ synthesis and stabilizing ZnO nanoparticles using triethanolamine optimized with response surface methodology

“…ZnO is an important nanophotocatalyst with low cost, luminescent and biocompatible antimicrobial properties [15][16][17]. ZnO nanotetrapods have been also prepared with potential applications for electron nanoconductors in multichannel optoelectronic devices [18].…”

Synthesis, Characterization and Biological Applications of Water-Soluble ZnO Quantum Dots

“…Decomposition/oxidation of organozinc precursors like Et 2 Zn or Cy 2 Zn in the air in the presence of alkylamines or amphiphilic hyperbranched polymers like stearate-modified polyether polyols allows the preparation of ZnO QDs with control over nanoparticles diameters and photophysical properties (Glaria et al, 2008;Richter et al, 2009). The hydrophobic nanomaterials prepared can however only be dispersed in organic solvents (THF, toluene) and are therefore not suitable for biological applications.…”