Reversible Pattern Formation through Photolysis
mediaposted on 15.08.2006 by Timothy R. Kline, Ayusman Sen
Media is any form of research output that is recorded and played. This is most commonly video, but can be audio or 3D representations.
We report a photolytic method to induce spatial and temporal patterning/deposition of particles at the micron scale on a time scale of seconds. Reversible pattern formation by negatively charged particles occur around micron-sized silver features on different substrates when exposed to UV light in the presence of aqueous hydrogen peroxide. Diffusiophoretic motion due to a spatially defined ion gradient accounts for our observations. Atomic force and optical microscopy, as well as conductivity measurements, support this hypothesis.