Glow-in-the-dark cement could illuminate dark highways Thursday, 19 May 2016

A researcher in Mexico has succeeded in creating cement that is capable of absorbing the sun’s energy during the day and glowing at night.

José Carlos Rubio from the University of San Nicolas Hidalgo estimates his light-emitting cement has a lifespan of 100 years.

Cement currently takes the form of dust that is added to water - in the case of non-hydraulic cement, this is calcium oxide, while in hydraulic cements, the “dust” is a mixture of silicates and oxides.

During the chemical reaction, the mixture turns into a gel-like substance, and crystal flakes are formed as unwanted sub-products. Hoping to eliminate this problem, Mr Rubio started looking at the micro-structure of the cement.

What he ended up inventing, however, was an inorganic geopolymer material, which has an amorphous to semi-crystalline structure with photoluminiscent properties.

Unlike the glow-in-the-dark polymers currently on the market, this geopolymer is highly resistant to UV light, allowing to last for a long time. It is also highly resistant to fire, electrically insulated, and has a high chemical resistance to a diverse number of compounds and organic solvents.

Because the material has adhesive properties when it is manufactured, it can be used as a cement, and adhered to metallic, ceramic, glass and composite surfaces. It can be produced at room temperature or at temperatures lower than 300 degrees Celsius, substantially reducing the production costs.

When the geopolymer is excited by UV light, it is able to emit, from the inner portion of its matrix, light which lasts around 12 hours. Depending on the photoluminiscent crystal used within the structure of the geopolymer, it is possible to adjust the colour of the emitted light.

This glowing geopolymer can be used to manufacture photoluminiscent ceramic materials, mortar, concrete and composites.

Structures which emit glow without requiring electricity may be useful in the signaling, traffic, electric, electro-mechanical, architectonic and decoration, construction, military, automotive, aeronautical, oil, and naval industries as well as alternative energy industries.