Callaghan Innovation Research Papers

Back to Research Papers

TitleIn situ synchrotron X-Ray absorption experiments and modelling of the growth rates of electrochemically deposited zno nanostructures
Publication TypeConference Paper
Year of Publication2007
AuthorsIngham, B., Lily B.N., Mackay J.R., White S.P., Hendy S.C., and Ryan M.P.
Conference NameMaterials Research Society Symposium Proceedings
Date Published2007
KeywordsAbsorption, Absorption spectroscopy, Chemical speciation, Conductive films, Deposit morphology, Deposition Parameters, Electrochemical currents, Electrochemical deposition, Electrodeposition, Ex situ, Experiments, Function of time, growth rate, Growth regime, High resolution electron microscopy, In-situ experiments, In-situ synchrotrons, In-situ XAS, morphology, Nanostructures, Nernst-Planck equations, Nucleation and growth, Optoelectronic applications, Reduction, Semiconducting zinc compounds, Synchrotron x rays, Synchrotrons, X ray absorption, Zinc oxide, ZnO, ZnO nanostructures
AbstractZnO is known to produce a wide variety of nanostructures that have enormous scope for optoelectronic applications. Using an aqueous electrochemical deposition technique, we are able to tightly control a wide range of deposition parameters (Zn2 concentration, temperature, potential, time) and hence the resulting deposit morphology. By simultaneously conducting synchrotron x-ray absorption spectroscopy (XAS) experiments during the deposition, we are able to directly monitor the growth rates of the nanostructures, as well as providing direct chemical speciation of the films. In Situ experiments such as these are critical to understanding the nucleation and growth of such nanostructures. Recent results from in Situ XAS synchrotron experiments demonstrate the growth rates as a function of potential and Zn2 concentration. These are compared with the electrochemical current density recorded during the deposition, and the final morphology revealed through ex Situ high resolution electron microscopy. The results are indicative of two distinct growth regimes, and simultaneous changes in the morphology are observed. These experiments are complemented by modelling the growth of the rods in the transport-limited case, using the Nernst-Planck equations in 2 dimensions, to yield the growth rate of the volume, length, and radius as a function of time. © 2007 Materials Research Society.

Back to top