posted on 2021-09-29, 18:11authored byMartin Wittmann, Astrid Ali, Thomas Gemming, Fernando Stavale, Juliane Simmchen
Colloidal
active matter is known for its sensitivity to external
conditions; for example, the swimming speeds depend strongly on substrates,
fuel concentration, and in the case of light-driven colloids, the
illumination. While these points are regularly considered, the nanoscopic
material properties of the motor bodies are often barely mentioned,
but they are highly influential in the case of photocatalysts. In
order to demonstrate the influence of subtle differences in chemical
composition and interfacing between the different material compounds,
we designed a system based on colloidal titania spheres asymmetrized
by different nanoscale cobalt oxide species. We examine how the material
properties and combinations lead to highly specific catalytic activity
and cross-relate the subtle differences to the typical active behaviors
of these complex materials.