DVFU: Ceramic transformers of light for the LED systems

2021: Optimization of structure and parameters of composite ceramic transformers of light

Materials scientists of Far Eastern Federal University (DVFU) in cooperation with the international team of researchers optimized structure and parameters of composite ceramic materials phosphors (Ce3+: YAG–Al2O3), solid state converters of light which can be applied in land and aerospace technologies. The LED systems on the basis of the developed materials are 20-30 percent more energy efficient than commercial analogs. The university reported about it on January 26, 2021.

Annually more than 15% of all world production of the electric power, in terms of money – about 450 billion dollars are spent for lighting. According to the road map on development of photonics to the Russian Federation, mastering of the LED equipment with efficiency more than 150 lm/W will allow to release up to 30% of the electric power by 2025.

On the basis of the received ceramic svetopreobrazovatel it is possible to make as compact energy efficient LEDs of a white luminescence (wLEDs), and the high-power (superbright) systems. This material is demanded in many applications of photonics − from portable projectors and endoscopes to laser TVs with diagonal more than 100 inches, lighting instruments for a car - and aircraft industry, megaconstructions, etc. Work is performed at a financial support of the Russian scientific fund.

Consumption of white LEDs (wLEDs) is more than a half from general consumption of LEDs of high brightness. Features of the production technology of organic phosphors for commercial white LEDs lead to the fact that the light-emitting diode quickly 'grows old', loses brightness and quality of a color rendition in use. We solved this problem, having created completely inorganic transformers of light in the form of composite keramik on the basis of the alyumoittriyevy pomegranate activated by Ce cerium: YAG, and thermal and stable phase of oxide of Al2O3 aluminum — the junior researcher of NOTs "Advanced Ceramic Materials" of department of industrial security of Polytechnical institute (school, PI) of Anastasius Vornovskikh's DVFU tells.

Composites are characterized by high rates of temperature durability and heat conductivity, maintain the high power of pumping, and generate bright this world without explicit thermal suppression of intensity of a photoluminescence. It allows to reduce the working temperature of the LED device more than twice in comparison with the commercial samples Ce: YAG: to 120÷70 of °C.

Composites, are synthesized by method of reactionary agglomeration in a vacuum of powders of initial oxides of aluminum, yttrium, cerium and gadolinium. Special attention in work is paid to identification of quantitative interrelation of the main disseminating centers — a residual time and Al2O3 crystallites – and spectroscopic properties of ceramic phosphors. Our svetopreobrazovatel conform to all requirements for wLEDs of the last generation − have long term of service, high efficiency of luminous efficiency and a color rendering index when preserving requirements to environmental friendliness of material and to its sizes — the project manager Denis Kosyanov, the director of NOTs 'Advanced Ceramic Materials' of department of industrial security PI DVFU notes.

Specialists of DVFU, Shanghai institute of ceramics and the Shanghai Institute of Technology, University of the Chinese academy of Sciences, Institute of chemistry of the Far East department of RAS and also Institute of chemistry of a solid body and mechanochemistry of the Siberian department of RAS took part in work.