Rute Ferreira (Researcher), Vānia Freitas (PhD Student) and Xue Bai (Post-Doctoral Fellow) are authors of the paper
The research team from CICECO, in partnership with researchers of Humboldt University of Berlin (Germany), Changchun University of Science and Technology (China) and the Federal University of Pernambuco (Brazil), developed a new LED that, in relation to the technology that is currently used, has better quality of white light, better rendering index and color temperature and better stability and constant brightness. The article "Efficient and tuneable photoluminescent boehmite hybrid nanoplates lacking activator centers metal for single-phase white LEDs" published in Nature Communications, one of the most prestigious scientific journals in the world, resulted from the development of an LED light which is similar to the light emitted by the sun, without the usual use of filters to make it more welcoming and to not interfere with the perception of environmental colors around. In addition, the new LED has been developed with non-toxic materials abundant in nature and which potentiates the reduction of manufacturing costs and consequently selling costs.
"To create this LED has been developed a new material formed by particles of nanometric dimensions consisting of an organic part, based on carboxylic acids, and an inorganic part made by a aluminum-based mineral" reveals Rute Ferreira, Researcher from CICECO / Physics Department of the University of Aveiro and coordinator of the study. The particles were then deposited on the surface of a commercial LED that emits ultraviolet light, "light that our material absorbs and converts into white light with high brightness."
But LEDs are not only developed thinking on the comfort that the respective use in lighting, whether inside or outside, can provide to the eyes. "Being the LEDs an alternative to conventional light sources, energy-favorable and more environmentally sustainable, it is expected that they will dominate the coming decades the lighting industry," says Rute Ferreira.
In this sense, and to provide for the massive use of a technology that has given this year's Nobel Prize in Physics to Isamu Akasaki, Hiroshi Amano and Shuji Nakamura for the invention of LEDs emitting blue light as energy-saving sources precursors, the group of hybrids organic-inorganic functional from CICECO developed white LEDs with inexpensive and environmentally friendly materials.
The 'recipe' of the new LEDs, unveiled by the team of Rute Ferreira, Xue Bai e Vânia Feitas, from the physics and chemistry departments, involves the use of a material that "is produced with inexpensive raw materials, non-toxic and that can is found in nature in ores, such as bauxite that have a high annual production of around 200 million tons. "Features that are "desirable from an industrial and environmental point of view."
On the contrary, says Ruth Ferreira, "the production of the current white LEDs containing lanthanide ions with commercial high production cost and being toxic, involves chemical purification and a highly complex recycling".