How smart surfaces could reduce glass  skyscraper cleaning and energy costs
AUTHOR : Sophia Laney

City skylines around the world are increasingly dominated by tall buildings constructed with thick­glass panels – but nanostructures that show extreme water repellency could help to combat the heating, cooling, and cleaning costs of maintaining these iconic, glazed facades. 

In my project I create surfaces that contain millions of structures (pillars or cones), which are approximately 1,000x  smaller than the width of a human hair.  Water hates being in contact with these nanostructures, as they are known.

When a water droplet hits the surface, it  immediately bounces or rolls off. As the droplet rolls off the surface, it picks up  any dust along the way, which results in a “self­cleaning” surface that is excellent for windows.  In addition to the water repellent  properties, I am also looking to coat the nanostructures with materials that are thermo­responsive – where the properties change due to heat. And so the self­cleaning windows become "smart" windows that are able, without energy, to control the heat going into and out of a glass skyscraper depending on the outside temperature.

A change to the size and distance between the nanostructures has a significant effect on the overall surface properties. Decreasing the distance between the structures, for instance, can generate a surface that is not only self­cleaning but also anti­reflective.  

Anti­reflective surfaces are ideal for solar cells as they reduce the amount of reflected light, thereby increasing the energy efficiency of the solar cell – which in turn could make the heavy costs associated with glass skyscrapers easier to manage. 

CATEGORY : Smart Materials