Computation-assisted understanding of high photovoltaic efficiency of lead trihalide perovskites
Project Status: 3 Approved without Funding
Duration in months: 24 months
Objective
The Project aim. Due to the continuous growth of energy consumption in the world, the search for renewable energy sources is one of the actual problems of the XXI century. Despite recent advances in the research of lead-halide organic-inorganic perovskites, many of the fundamental causes of their record-breaking efficiency when converting sunlight into electricity remain unclear. In the framework of this project using the computer simulation methods a number of hypotheses will be tested, the confirmation or refutation of which will clarify the reasons for the effectiveness of the compounds under investigation. The obtained results will allowdevelop the practical recommendations for new materials design with predetermined properties for use in solar energy. Current status. At present time there is a continuous search for efficient photovoltaic materials and one of the promising material for this purpose is the lead-halide organic-inorganic perovskites. Such interest is caused by their relativelow cost, easein production and record levels in conversion of solar energy into electricity. Organic-inorganic perovskites consist of anionic inorganic solid frame (PbI3(-)) and small organic cations located within the "cell" frame. Organic-inorganic perovskites combine the properties of a solid semiconductor and ionic liquids, thereby demonstrating the intriguing and unusual properties. There is a lack of understanding of the relationship and the correlation between the structure of perovskites and their properties such as the effective absorption of light, the giant value of the dielectric constant, high polarizability at room temperature, a record long lifetime of the excited and the diffusion length of the charge carriers. The project’ influence on progress in this area.The proposed study based on computer simulation methods provide a deeper fundamental understanding of the lattice dynamics and electronic properties of perovskites, which determine their effectiveness as a material for solar energy conversion. The resulting data will have predictive power for the design of new materials with predetermined properties. The participants’ expertise.Team members participating in the implementation of this project, have a rich experience in computer modeling of materials. Their qualification is confirmed by numerous publications in international high-ranking journals and presentations at international conferences. Head of the project and the foreign collaborator has longtime successfully cooperation experience in the field of modeling the properties of materials for solar energy conversion, as evidenced by a number of joint publications. Expected results and their application.Understanding the fundamental processes that determine the effectiveness of these compounds as the working elements of the solar cells will allow us not only describe the properties of existing materials, but also point out the way for the development of new, cheaper, more efficient and environmentally friendly materials for solar energy conversion. Here we are trying to expand our view of the perovskite semiconductor materials. These perovskites form a new class of materials that combine the properties of both solids and ionic liquids. Detailed study of these materials and their variations will be accompanied by finding a more general class of materials that combine the useful properties of both organic and inorganic subsystems. Meeting the ISTC goals and objectives. Since the project involves professionals with expertise in the field of weapons of mass destruction, and the project itself has only peaceful purposes, it is consistent with the ISTC goals. Scope of activities. The following activities will be implemented under the Project:
- Calculation the trajectories of motion of atoms in the perovskite structure at different temperatures using method of ab initiomolecular dynamics;
- - Analysis of the life time of the electronic excitations and the diffusion length of charge carriers at different temperatures;
- - Analysis of the dynamics of the excited states of a first-principles simulation results perovskites to identify the presence or absence of inorganic photodissociation time frame of three-iodide anion lead to mono-lead iodide anion and neutral di-iodide of lead, followed by a return to the original configuration;
- - A study similar compounds studied lattices with modified stoichiometry by replacing elements onto Pb > Sn, I > Br > Cl, etc.;
- - Development of the recommendations on the preparation and processing of crystals, improving the properties of materials for modern solar energy converters.
