Nanotechnology and the self-cleaning toilet

The best inventions are those that integrate so well into life that it becomes hard to imagine what life would have been like without it. Despite the phrase “best thing since sliced bread”, I personally can imagine life quite well without it. In fact, whole loaves of bread are often cheaper and better than their sliced counterparts and when it get right down to it, slicing bread is not really that hard. Inventions and discoveries like electricity, the refrigerator, toothpaste and the toothbrush, flushing toilets fit nicely in the “best inventions category”.

Nevertheless, the nanoparticle coating developed by researchers at the University of New South Wales is most definitely, “the best thing since sliced bread”.

The coating contains nanoparticles of titanium dioxide. Titanium dioxide is activated by ultraviolet light and gives a powerful oxidising effect. However, to make the coating work with indoor lighting, the researches modified it with some other elements. Tests of the coating on glass show that it can kill E. coli using the light of an indoor lamp.

Somehow it is comforting to know that my toilet bowl is actively killing bugs, rather than a sitting there providing a safe haven.

From: Best Syndication

Nano Technology may make cleaning Toilets a thing of the Past (excerpt)
February 7th, 2006

...Researchers from the University of New South Wales, Australia, are developing a coating that may make cleaning bathrooms less of a chore.

The lead researchers, Professors Rose Amal and Michael Brungs of the ARC Centre for Functional Nanomaterials, are hoping to apply a tiny coating of titanium dioxide particles to keep the toilets clean. Currently titanium dioxide is being used on outdoor items like self-cleaning windows.

How does it work? According to the scientists, ultraviolet light below a specific wavelength causes electrons to excite, and this gives the effects of oxidation. This oxidation disinfects better than commercial bleach. It makes it better for sanitation as it is continually cleans, instead of waiting for the janitor.

To further keep the bathroom clean, nanoparticles kill the microbes and removes organic compounds. The titanium dioxide contains ‘superhydrophilicity’. Superhydrophilicity makes it so that liquid droplets do not form on the surface. It makes the liquid run off, washing the toilet in the process.

The researchers are faced with one dilemma: making the titanium dioxide coating work indoors. The coating is activated by ultraviolet sunlight, and they will need to be able to activate the titanium dioxide with indoor lighting. They are trying to modify the chemical compound by adding other elements like iron or nitrogen so it can use light of a longer wavelength.

Good news: Currently the researcher’s have been able to get glass coated with the new nanoparticles to kill Escherichia coli using light from an indoor lamp. They have done this in lab-trials ...