Picture of the Month - December 2018
Here you see current insights into the research of the LaMa groups. A collection of the former pictures can be found in the Gallery.
Electrochemical Deposition of Hierarchical ZnO Nanostructures
We study the electrochemical deposition of ZnO thin films in various structures onto conductive substrates [1] and they can be used as electrodes in photoelectrochemical devices or batteries [2, 3]. A well-functioning electrode requires a fast charge transport, good accessibility of its surface for e.g. liquid solutions and a high surface area [2, 3]. While the first two requirements are met for ZnO nano rods, the last requirement is not. Thus, we were looking for an electrode structure that maintains a fast charge transport and good surface accessibility but also has a large surface: “nano corn-dogs”. Highly porous ZnO is electrodeposited onto the surface of nano rods pre-deposited in a first independent step. By setting deposition parameters one can control the structural properties, e.g. a deposition of highly porous ZnO only at the bottom part (close to the substrate) of the nano rod or at the top part (solution side) of the nano rod, only . This technique allows the specific design of nanostructured ZnO electrodes depending on the specific demands.
[1] C. Lupó, D. Schlettwein. J. Electrochem. Soc. 166(1), D3182-D3189. 2019. DOI: 10.1149/2.0231901jes
[2] R. Ruess, S. Haas, A. Ringleb, D. Schlettwein. Electrochim. Acta 258, 591-598. 2017. DOI: 10.1016/j.electacta.2017.11.102
[3] M. Stumpp, D. Damtew, D. Stock, K. Hess, D. Schröder, D. Schlettwein. J. Electrochem. Soc. 165(10), D461-D466. 2018. DOI: 10.1149/2.0941810jes
We still hold the copyright of our SEM image of the nanostructures, the “real” corndogs stem from [Jonathunder, GFDL 1.2, https://commons.wikimedia.org/wiki/File:CornDog.jpg]
This picture was submitted by Prof. Dr. Derck Schlettwein.
