May 23 2018
A synthetic SensoGlow™ material capable of detecting the quality and quantity of ultraviolet radiation from the Sun or other sources has been developed by researchers from the University of Turku. This material makes it viable to create an economical, versatile, and long-term UV radiation detector which can be used to track the UV radiation dose with a mobile app, for instance.
Image credit: The University of Turku.
UV radiation is known to cause many eye and skin diseases such as cancer. Thus, it is vital to have a simple technique for detecting the quality and quantity of UV radiation from, for instance, the Sun.
This is currently achieved by using mainly organic molecules that change colour under UV radiation. The downside of using these molecules, however, is their poor durability which is due to the fact that the colour changes involve reorganisation of the molecular structure. Organic molecules are thus not very long-lasting for this purpose.
Mika Lastusaari, Docent in Inorganic Chemistry at the University of Turku
Inorganic Materials Chemistry research group of the Department of Chemistry at the University of Turku has created a synthetic SensoGlow™ material which is based on natural hackmanite and can alter color based on the quality and quantity of UV radiation. This material can be tweaked to respond to UVA, UVB, or UVC radiation levels, in addition to the UV index of the Sun.
“The colour change of the SensoGlow™ material isn’t based on structural change but on the electron storage in the material which makes it more durable than organic alternatives. Since the colour change is based on electron storage, the process is reversible. When the material is removed from UV radiation, electrons return to their ground state, and the color of the material returns to normal," describes Isabella Norrbo, who is working on her doctoral dissertation in the research group.
Due to these properties, the material can be used numerous times. Furthermore, the production of SensoGlow™ material is very economical owing to the fact that it is made up of common elements.
“We believe that it is possible to produce an affordable, versatile, and long-lasting UV radiation detector that could function in everyday use to monitor your UV radiation dose. This monitoring could be done using a mobile app, for example,” says Lastusaari.
The color intensity of the SensoGlow™ material matches the dose of radiation. The material could, for instance, be applied as a sticker attached to a watch. The amount of radiation could be measured by clicking a picture of the sticker using a mobile phone, and a mobile app would show the present value of the UV index.
Besides conducting experimental research, the team scrutinized the color change via computational techniques in a collaborative research that was performed by the University of Lyon in France. The computational results validated the experimental findings.
Through these results, we were able to gain more information on the mechanism related to the color change, and on color reversion. In the experimental research on the mechanism of the color change, we had help from the Department of Physics of the University of Turku, Solar Simulator Finland Ltd., and Uppsala University.
Mika Lastusaari, Docent in Inorganic Chemistry at the University of Turku
The study was funded by Business Finland, the Academy of Finland, Nordic Energy Research, Turku University Foundation, University of Turku Graduate School, Jenny and Antti Wihuri Foundation, Finnish Cultural Foundation (Varsinais-Suomi Regional Fund), and French agency ANR.
The research paper was reported in the journal Materials Horizons.