One‐Step Synthesis of Stoichiometrically Defined Metal Oxide Nanoparticles at Room Temperature

Abstract

A great variety of metal oxide nanoparticles have been readily synthesized by using alkali metal oxides, M(2)O (M is Na or Li) and soluble metal salts (metal chlorides) in polar organic solutions, for example, methanol and ethanol, at room temperature. The oxidation states of the metals in the resulting metal oxides (Cu(2)O, CuO, ZnO, Al(2)O(3), Fe(2)O(3), Bi(2)O(3), TiO(2), SnO(2), CeO(2), Nb(2)O(5), WO(3), and CoFe(2)O(4)) range from 1 to 6 and remain invariable through the reactions where good control of stoichiometry is achieved. Metal oxide nanoparticles are 1-30 nm and have good monodispersivity and displayed comparable optical spectra. These syntheses are based on a general ion reaction pathway during which the precipitate occurs when O(2-) ions meet metal cations (M(n+)) in anhydrous solution and the reaction equation is M(n+) + n/2 O(2-) --> MO(n/2) (n=1-6).

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

“…21), it is worth noting an alternative stoichiometric strategy to metal oxide NPs by low temperature routes -the 'direct liquid phase participation' pathway developed by Morris and co-workers. 199 In this case, the oxygen source is Na2O, which reacts with a MClx precursor in a direct stoichiometric manner in alcohol solvents. Whilst the metal oxide phase precipitates as small NPs the by-product NaCl remains dissolved in the alcoholic solution.…”

“…Whilst the metal oxide phase precipitates as small NPs the by-product NaCl remains dissolved in the alcoholic solution. The process can be used for a variety of metal oxide products such as Cu2O, WO3 or even ternary phases such as CoFe2O3, 199,200 with additives (e.g. alkylamines and oleic acid) enabling improved monodispersity of the NPs.…”

Growth, structure, morphology, and magnetic properties of Ni ferrite films

“…In particular, Ni ferrite (NiFe 2 O 4 ) films with spinel structure were currently of great interest due to their high magnetic permeability, high resistivity, and low losses, making itself a promising material for high-frequency applications. Many methods have been carried out to fabricate ferrites, such as molecular beam epitaxy [1], pulsed laser deposition [2,3], spin-spray [4,5], sol–gel [6], electrochemical deposition [7], direct liquid phase precipitation [8], hydrothermal growth [9,10], and sputtering [11,12]. Researches on structural and magnetic properties of ferrites have been devoted recently.…”

Non-solvolytic synthesis of aqueous soluble TiO2 nanoparticles and real-time dynamic measurements of the nanoparticle formation

“…The synthesis reaction and subsequent treatments are carried out under ambient [31-33] or solvothermal conditions [11,34-38]. Recently, a novel solution-based method to synthesize nanostructured metal oxides - the direct liquid phase precipitation (DLPP), has been developed by us [39]. In this approach, a great variety of metal oxide NPs can be easily prepared by exchange of anions of a corresponding metal salt (e.g., CuCl, ZnCl 2 , FeCl 3 , and SnCl 4 ) with alkali metal oxides in non-aqueous conditions.…”