Optimum between purification and colloidal stability of ZnO nanoparticles

Analysis of Particle Size Distributions of Quantum Dots: From Theory to Application

“…Regarding smallest nanoparticles such as QDs, it becomes obvious that a core size distribution is hardly accessible via DLS due to the fact that the ligand shell is no longer negligible (Marczak R. et al, 2010;Oshima H., 2009;Reindl A. and Peukert W., 2008). Additionally, the scattering intensity of particles below 10 nm is small, causing a low resolution of commercial devices in the size range of interest between 1 and 10 nm.…”

EPD-deposited ZnO thin films: a review

“…A wide number of authors have studied the surface reactivity of ZnO colloids synthesized following the method reported by Bahnemann et al [56][57][58][59][60]. Most of these works came to the conclusion that surface defects of the ZnO nanoparticles were passivated by acetate ions from the synthesis procedure, and that it is the presence of these acetate groups what enhances the stability of the ZnO nanoparticles in the alcoholic media, acting as spacers and quenching the attractive van der Waals forces.…”

In-Situ Versus Post-Synthetic Stabilization of Metal Oxide Nanoparticles

“…The DLVO theory has thus been applied in a number of cases to describe the behaviour of nanoparticulate systems (Schwarz & Safran, 2000;Tadmor & Klein, 2001;Reindl & Peukert, 2008;Marczak et al, 2009;Segets et al, 2011). However, some special aspects need to be taken into account when attempting to describe dispersions of nanoparticles below 20 nm in size by means of DLVO theory: On the one hand, the distance dependence of the attractive and repulsive forces is strongly dependent on particle size already in the classical DLVO concept (Verwey & Overbeek, 1948).…”

“…The application of the DLVO concept to such small particles generally leads to interaction potentials of only a few k . T, which results in only small changes between a stable and an unstable system, making the prediction of the stability of a system a challenging task (Marczak et al, 2009;Segets et al, 2011). Moreover, the minimum is also shifted in position towards smaller interparticle distances and thus, the description of the particles as solid, spherical systems with defined interface becomes inappropriate.…”

“…Moreover, it is clearly visible that the adsorbate layer formed by solvent adsorption also has a noticeable effect on the energy barrier despite the relatively large particle size of 100 nm, further increasing the stability of the system. Such core-shell models have been applied also to other systems in the meantime (Marczak et al, 2009;Segets et al, 2011). On the other hand, an extension of the DLVO theory has been proposed, leading to the socalled XDLVO concept, in the works by van Oss et al (van Oss et al, 1987(van Oss et al, , 2003.…”