UG scientists work to develop advanced infrared phosphors

Researchers from the University of Gdańsk, under the direction of dr hab. Sebastian Mahlik, prof. UG, intend to create modern infrared luminescent phosphors that could be used, among others, in the food industry or medicine. The project entitled. 'Perovskite and Broadband Infrared Phosphors for Lighting-Emitting Diode Applications' is implemented under the Polish-Taiwanese Research Cooperation (2020).

NCBiR together with the Ministry of Science and Technology in Taipei settled the 8th competition within the Polish-Taiwanese Research Cooperation (2020). The project of dr hab. Sebastian Mahlik, prof. UG entitled. "Perovskite and Broadband Infrared Phosphors for Lighting-Emitting Diode Applications", is on the shortlist of four projects recommended for funding.

Test your food with your smartphone

Infrared technology, i.e. light invisible to the human eye, continues to offer new possibilities. As technology develops, light-emitting diodes (LEDs), like all electronic components, are becoming ever more miniature. As a result, they can be used as light sources in micro-spectrometers placed in a smartphone, for example, to test food for nutritional value or to measure body fat levels. The critical element of such a device, on which researchers from the Faculty of Mathematics, Physics and Computer Science are working, is an appropriate phosphor, which converts light emitted by the diode of one colour - usually in the visible range - into infrared light of a wide spectral range (i.e. emitting many wavelengths of infrared light). Only a phosphor with such properties will give the device its full practical potential.

- 'The aim of our new project is the fabrication and characterisation of modern phosphors emitting light in the visible and infrared spectrum, excited by light from luminescent diodes,' - says dr hab. Sebastian Mahlik, prof. UG. - 'We want to create modern infrared luminescent phosphors for future applications, e.g. in the food industry or medicine. In our research, we focus on LED light sources, on improving their emission spectrum using a phosphor, as well as on their miniaturisation, so that they can be installed, for example, in a smartphone.'

The project is a continuation of joint research conducted by the group of prof. R.S. Liu at the National University of Taiwan and the group of dr hab. Sebastian Mahlik, prof. UG from the Faculty of Mathematics, Physics and Computer Science, previously led by prof. Marek Grinberg, within the project 'Narrow Band Phosphors for the Application in Lighting and Backlighting of Light-Emitting Diodes', which aimed at improving white LED light sources so that the colour rendering of illuminated objects is better and the light itself is more pleasant to perceive.

The research will be conducted in two directions:

  1. Synthesis and characterisation of broadband infrared phosphors for oxide-based LEDs doped with transition metal ions primarily with Cr3+ ions;
  2. Synthesis and characterisation of perovskite quantum dots as potential phosphors.

The University of Taiwan is one of the leading research centres engaged in the synthesis of inorganic phosphors, with unique capabilities such as high-pressure synthesis and access to advanced methods of structural studies. In turn, the group at the University of Gdańsk has excellent facilities for spectroscopic studies of phosphors: such as studies of luminescence kinetics as a function of temperature, or a unique method of spectroscopy under high pressure. In this method, changes in the optical properties of materials are observed under the influence of pressure of hundreds of thousands of atmospheres - a pressure sufficient to displace atoms in the crystal structure.

The role of the University of Taiwan will be to synthesise new materials, as well as to make demonstrators of working devices, while the role of the University of Gdańsk is to study the properties of synthesised phosphors, as well as theoretical modelling of new materials.

About the Polish-Taiwanese competition of NCBiR and the Ministry of Science and Technology in Taipei

Bilateral Polish-Taiwanese competitions are conducted under the scientific-research cooperation between the National Centre for Research and Development in Warsaw and the Ministry of Science and Technology (MOST) in Taipei. They aim to strengthen contacts between the Polish and Taiwanese scientific communities and to establish mutually beneficial research co-operation.

Elżbieta Michalak-Witkowska/Press Office of University of Gdańsk