Real-Time Monitoring of the Nucleation and Growth of ZnO Nanoparticles Using an Optical Hyper-Rayleigh Scattering Method

Abstract

Incoherent nonlinear hyper-Rayleigh scattering (HRS) has been applied to monitor the different stages in the synthesis of sub-10 nm ZnO nanoparticles. During time-resolved investigation of the ripening process, we measured an increase in the particle hyperpolarizability, βZnO, with increasing particle size. Millisecond time resolution measurements revealed regions of prevalent nucleation, growth, and ripening. Using the size-dependent hyperpolarizabilities, a new general approach is introduced for the quantitative determination of nucleation, growth, and ripening rates via in situ HRS measurements. The derived solubility also allowed the determination of reasonable values of the ZnO surface energy.

Process Engineering of Nanoparticles Below 20 nm—A Fundamental Discussion of Characterization, Particle Formation, Stability and Post Processing

“…As it becomes clear from Fig. 3b, the bimodal PSDs derived directly from the bimodal absorbance spectrum show an excellent agreement with the expected PSDs artificially generated from the density distributions of the individual, un-mixed samples [63,65].…”

“…Validation was first realized for ZnO QDs using a direct comparison between the calculated results with an expected PSD derived from transmission electron microscopy (TEM) [63,65]. Additionally, bimodal size distributions were generated artificially by mixing a suspension of small nanoparticles with a suspension of large particles in different volume ratios.…”

Safety Assessment by Multiphoton Fluorescence/Second Harmonic Generation/Hyper-Rayleigh Scattering Tomography of ZnO Nanoparticles Used in Cosmetic Products

“…Both types of scattering have been reported to occur for ZnO NPs at considerable intensities [36,37]. They can be identified and distinguished from autofluorescence because of three basic properties: (i) SHG as well as HRS signals are generated instantaneously, i.e.…”

Size and Shape Effect on Biomedical Applications of Nanomaterials

“…Non linear optical properties of nanostructured materials [16][17][18] can be useful in optoelectronics. Size and shape dependent properties of noble nanomaterials are resulting in the strong scattering and absorption of light [19][20][21] due to large optical field enhancement, however in semiconductors, due to the confinement of the electronic motion to a length scale that is comparable to or smaller than the length scale characterizing the electronic motion in bulk semiconducting material [22][23][24].…”