from Metropolis Magazine -
Self-Cleaning Tiles
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from Materials Today -
Nanoparticles help paint resist germs
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The first, a self-cleaning coating on ceramics which both absorbs pollutants and breaks down organic dirt by the action of ultra-violet radiation.

Also see previous posts here and here on the same technology but applied to clear glass panels.

While the second uses the antiseptic properties of metal particles to combat the growth of disfiguring micro-organisms on painted surfaces.

Still eagerly waiting for such technologies to be transferred to outdoor sculptures or even as a protective coating on historic monuments.
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