Synthesis of ZnO Nanoparticles in 2-Propanol by Reaction with Water

Abstract

We report on the synthesis of ZnO particles from Zn(CH(3)CO(2))(2) in 2-propanol as a function of the concentration of water, in the absence of a base such as NaOH. Particles with diameters of 3-5 nm are formed depending on time, temperature, and water concentration. The nucleation and growth are slower than in the presence of NaOH, and at longer times the increase in particle size is dominated by diffusion-limited coarsening. The rate constant for coarsening increases with increasing water concentration up to 150 mM, above which the rate constant is 1.1 x 10(-4) cm(3) s(-1), independent of the water concentration. The width of the particle size distribution decreases with increasing water concentration, and at 250 mM water, the full width at half-maximum of the distribution function is essentially the same as for the synthesis of ZnO using NaOH as a reactant. The temperature dependence of coarsening is determined by the bulk solubility of the ZnO nanoparticles and yields an apparent activation energy of 1.12 eV. This is significantly larger than the activation energy of 0.35 eV for coarsening of ZnO from 1 mM Zn(CH(3)CO(2))(2) in 2-propanol with 1.6 mM NaOH.

Effect of water content on growth and optical properties of ZnO nanoparticles generated in binary solvent mixtures by micro-continuous flow synthesis

“…From the inset graph in Fig. 4, we can clearly observe the increase of the wavelength of absorption peaks with enhancing water contents, which was associated with particle growth [46]. It is already reported that the dependence of particles size on the optical absorption spectra can be determined by using the effective mass model; details of the calculation can be found in Ref.…”

Synthesis, Self-assembly and Optoelectronic Properties of Monodisperse ZnO Quantum Dots

“…Sol-gel method Sol-gel method, one of the widely used wet chemical methods in synthesizing various nanomaterials [15,[73][74][75], has been used for fabrication of ZnO QDs [26][27][28][29][30][31][32][33][34][35][36][37][38][39][40]. Among a number of reports on fabrication of ZnO QDs over the past decades, sol-gel method was the mostly used one due to its simplicity and cheapness.…”

“…By far, various kinds of synthetic approaches have been realized in fabricating such small ZnO QDs, which can be roughly divided into chemical methods and physical methods. Chemical methods involves sol-gel method [26][27][28][29][30][31][32][33][34][35][36][37][38][39][40], hydrothermal growth [41][42][43][44], thermal decomposition [45][46][47][48][49][50], electrochemical method [51][52][53][54], while physical methods involves PLA or PLD [55][56][57][58][59], MOCVD [60][61][62][63], sputtering [64][65][66], FSP method [67][68][69][70] and VPT deposition [71,72]. At present, all the methods can be divided into two parts as follow:…”

Solution‐Processed Electronics Based on Transparent Conductive Oxides

“…First, nanoparticles of transparent conductive oxides are synthesized, with suitable organic encapsulants as appropriate. For example, zinc oxide is easily synthesized in nanoparticle form (Figure 9.1) [10][11][12]. This may be achieved by precipitating zinc oxide out of, for example, zinc acetate in an isopropanol bath by addition of sodium hydroxide.…”