Many-electron photovoltaic processes in low-dimensional systems and conversion of solar energy

Project Manager:

Doctor of Physics and Mathematics Matrasulov D.U.

Performers:

professor, Doctor of Physics and Mathematics Oksengendler B.A.

Trainee researcher Yusupov J.R.

The work is dedicated to:

This project is aimed at investigating the role of quantum-size effects in many-electron photovoltaic processes, which form the basis of the mechanism for highly efficient conversion of solar energy. In particular, for the current period a model of an experimentally observed recently observed sharp increase in the through
photocurrent in solar cells based on “quantum dot-polymer” composites. The model is based on the idea of ​​resonant tunneling of charge carriers through the local level of the organic layer between the quantum dot and the polymer matrix. In addition, the influence of interference of two ways of electron transfer from
valence band in the conduction band at the quantum dot, with the coherent addition of ionization of which Fano resonance can be realized, which leads to an increase in the internal efficiency of the light transformation and can be the basis for increasing the efficiency of the solar cell on the basis of the multiple exciton generation (MEG) effect.

Objects of research:

Hybrid solar cells, polymers, quantum dots, perovskites.

Goal:

The aim of this project is to study theoretically the process of exciton generation, charge separation, and carrier dynamics in hybrid solar cells based on polymers, quantum dots, and perovskites. In particular, the project provides for the study and explanation of the mechanism of multiple exciton generation in solar cells based on quantum dots, charge separation and transport in photovoltaic polymers, and the dynamics of charge carriers in solar cells based on perovskites. The research will use both quantum mechanical and nonlinear models based on the theory of solitons.

The main task

The main objective of this project is to study the dynamics of the charge, including their transport, splitting and recombination in solar cells of the third generation based on polymers, quantum dots, perovskites, and their hybrids.

The creation of highly efficient, flexible and commercially competitive solar cells of the third generation is an urgent task for a number of disciplines of modern science, such as condensed matter physics, polymer chemistry, materials science, photovoltaics and others. To date, there have been several ways of solving this problem, each of which has become a separate direction in modern photovoltaics. The first of such directions is the creation of flexible and cheap solar cells based on polymers and their hybrids with carbon nanostructures. Here we are talking about the creation of photovoltaic materials, which possess very small scales, flexibility, ecological safety, but with a low efficiency (about 8-12%). Because of the significant low cost and compactness, such solar cells can compete quite competently with those based on silicon. Studies on this topic were separated into a separate direction, called organic photovoltaics. The second direction, aimed at solving the problem of creating solar cells of the third generation, is the development of photovoltaic materials, the efficiency of which exceeds the so-called Shockley-Kuiser barrier, i.e. 45%. Currently, the most likely candidate for this solar cell is materials that allow multiple generation of excitons upon absorption of one photon, i.e. solar cells based on quantum dots. However, the solution of such a problem is still far from being outside the laboratory implementation due to the complexity of the technology and its high cost. And, finally, the third, and at the moment, the most promising candidate for solar cells of the third generation, capable of replacing silicon – are solar cells based on perovskite materials. This is confirmed by the boom observed in recent years in the literature on this area and the monotonous growth of the efficiency of these materials from 7 to 21% during the last 4 years. The study of the microscopic mechanisms of the formation, separation and transfer of charges in each of the varieties of the above materials is the main objective of this project.