Microfabrication was employed to pattern silver (Ag) on a gold (Au) surface. The two metals served as bimetallic heterogeneous catalysts for the heterogeneous decomposition of H2O2. Silver was the cathode, carrying out H2O2 reduction (to water) and gold the anode carrying out H2O2 oxidation (to oxygen). Both protons and electrons are created at the anode (as a part of the reaction) and migrate to the cathode (migration of ions is a current) where they are consumed. An electric field is thereby established (migration of ions obeys Ohm's law), which passively pumps fluids through electroosmosis. Electrophoresis is also present as either an additive component to the electroosmotic flow or results in pattern formation (occurs at point where electroosmosis is equal and opposite to that of electrophoresis). Herein, we describe the testing of the electrokinetic model, chemical methods to tune the tracer behavior (convection to pattern formation) and design of asymmetric patterns through microfabrication.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering