Scientists at Tomsk Polytechnic University have developed a method to transform natural materials such as chalk, limestone, and even marble into ultra-bright light sources at a low cost.
According to Ceramics International magazine, the innovative method allows for the production of bright red luminescent materials from readily available natural raw materials, with the innovators using marble, chalk, limestone and dolomite instead of rare and expensive chemical elements.
The press office of the Russian Ministry of Education and Science notes that this method involves the synthesis of calcium aluminates—materials widely used in the production of luminescent compounds for road markings and hazard warning signs. Their production typically requires the use of pure and expensive chemicals such as europium and dysprosium, making the process costly.
However, researchers from Tomsk Polytechnic University used natural ores as a source of calcium, and manganese oxide combined with boric acid acted as a fluorescent activator. The resulting samples exhibited surprising behavior: in daylight, they appeared as ordinary brown powder, but under ultraviolet light, they glowed a bright red with a wavelength of approximately 654 nanometers. This range is particularly noticeable to the human eye.
According to Professor Andrei Mostovshikov of the Chemical Engineering Department at Tomsk Polytechnic University, the main advantage of this technology lies in its simplicity and predictability. By knowing the impurities present in natural raw materials, scientists can precisely adjust the brightness and color of the glow. Iron impurities have been shown to reduce brightness, while magnesium enhances it. Marble is the best source of calcium, and thanks to its homogeneous structure and magnesium content, it produces an intense glow.
This innovation will be used to produce inexpensive and durable illuminated safety signs, indicators, and emergency lights that do not require complex and costly production.
