Swimming microengines made from platinum and iron are highly
efficient in removing organic pollutants from water using hydrogen peroxide.
Researchers from the Max Planck Institute for Intelligent
Systems in Stuttgart have developed a new method for the active degradation of
organic pollutants in solution by using swimming microengines. The mobile
microcleaners consist of an outer iron and an inner platinum layer, thereby
combining two functionalities. Hydrogen peroxide, which must be added to the
contaminated solution, acts as fuel for the platinum micromotors and as reagent
for degrading organic pollutants on the iron layer. Not many methods for the
successful cleaning of polluted wastewaters exist. The Fenton reaction, one of
the most popular advanced oxidation processes for the degradation of organic
pollutants, relies on spontaneous acidic corrosion of the iron micromotor
surface in the presence of hydrogen peroxide. The scientists report that the
oxidation of organic pollutants achieved by a swarm of these self-propelled
microjets is twelve times higher than when using immobile iron microtubes.