In the increasingly near future our homes will be equipped not with simple windows, but with windows photovoltaic, perfectly transparent and capable of absorbing energy, transforming it into electric current.
This perspective is confirmed by the research conducted by the Ecole Polytechnique Fédéral of Lausanne, in collaboration with the Tokyo Institute of Technology, the results of which were published in the journal Physical Review Applied.
Tellurite glass
Il glass it is an amorphous solid, which means that it does not have a crystalline lattice, since the molecules that compose it are not arranged in an orderly manner. Glass is commonly made of silicon dioxide polymers (SiO2), but it can be composed of other types of oxides, including tellurium dioxide (TeO2).
And it is precisely the tellurite glasses, mainly made up of the oxide just mentioned, that interest Swiss researchers.
How do you approach the production of photovoltaic windows?
When exposed to the pulsed light of femtosecond lasers, tellurite glass partially changes its molecular structure, moving from a disordered structure to a series of "photoconductive" patterns. A change that affects the optical properties of the material. In detail, the energy of the laser rays determines the formation of tellurium nanocrystals, alternating with tellurium dioxide molecules, which allow the passage of electric current.
This discovery appears to realize the potential of photovoltaic windows, as researchers have verified the possibility of engrave long-lasting patterns on the surface of the tellurite glass. An operation that allows you to generate electric current, thanks to the exposure of tellurium (semiconductor) to different wavelengths (from ultraviolet to the visible spectrum).
The real innovation, compared to the panels, is represented by the transparency of the material. Although this is only the first phase of research, the prospect of transparent photovoltaic windows fascinates both architects and builders as well as customers who are more sensitive to the issues of sustainability and energy saving.
Source: Repubblica.it
