Ryota Kobayashi, a student at Kyoto University, won the 3-minute oral presentation competition and the Light Conversion award with the topic "Structural optimization and implementation of superconducting THz source based on the anisotropic dielectric model".

 

At the same time, the award for the best poster presentation, established by the Lithuanian Quantum Technology Association "Quantum Lithuania", went to Titas Klepeckas, an engineer at the FTMC Department of Molecular Derivatives Physics, and a second-year master's student at the Faculty of Physics of Vilnius University. His topic was "Charge Generation and Drift Dynamics in Novel PM6:Y6 Organic Solar Cell Blends".

 

Congratulations to the winners and best wishes for a successful scientific journey!

 

 

 

We are especially happy for our colleague Titas Klepeckas. He studies organic solar cells and the most important part of them - the so-called active layer, which converts sunlight into an electric current.

 

This is particularly important because, although organic solar cells are only slightly (>3%) behind conventional semiconductor-based solar cells in efficiency, they have not yet been produced industrially. The reason for this is one of the shortcomings of organic solar cells: the dynamics of the charge carriers (the electrons and holes that carry the electric charge and allow the generation of an electric current) in these layers is not yet fully understood.

 

While conventional semiconductor solar cells are usually composed of a single material, in organic solar cells two materials are important: the donor (which gives up electrons when they are extracted from the material) and the acceptor (the material which accepts the free electrons extracted). When the organic layer is excited, the electron and the hole are strongly bound to each other, so it is these materials that help to separate them from each other.

 

 

 

"There has been no comprehensive research worldwide that has looked at how the charges are generated and how they move depending on the different ratios of the two materials - donor and acceptor.

 

So in our work, for example, we choose four times more donor than acceptor for solar cells - or vice versa. By varying the ratio of donor to acceptor in different proportions, we observe how the efficiency of these active layers varies, how the free charges are generated, how they can be extracted from the varying donor-acceptor ratio (and we do this by applying an electric field to the layer).

 

Since there are two different theories on the dynamics of charge separation that we are studying, and one of them is about the ratio of materials, we are sort of testing them, providing additional information," says one of the APROPOS 19 winners T. Klepeckas.