New nanoparticle coatings could make scrubbing mucky toilets and sponging grimy baths a thing of the past, according to University of
Nanoscale particles of titanium dioxide are currently used on outdoor surfaces such as self-cleaning windows. The particles absorb ultraviolet (UV) light, exciting electrons and giving them bleach-like oxidising properties that can kill microbes and break down organic compounds.
Surfaces covered in the particles also exhibit superhydrophilicity, meaning water runs straight off without forming droplets, cleaning as it goes.
The challenge facing the team from the ARC Centre for Functional Nanomaterials is modifying the titanium dioxide nanoparticles to operate with indoor light. They are experimenting with adding other elements such as iron and nitrogen so they can absorb light at longer wavelengths.
Lab trials show that glass coated with the new nanoparticles can be activated by visible light from a lamp to kill Escherchia coli (E. coli), a common cause of food poisoning.
The team say the enhanced surfaces will require less chemical agents to clean. They estimate that the surfaces will be available for testing outside the laboratory in a year.