Mechanisms of charge transfer dynamics in materials for green energy

Main applicant: Biplab Sanyal, Division of Materials Theory
Project title: Mechanisms of charge transfer dynamics in materials for green energy
Grant amount: 1 125 000 SEK​
Funder: Swedish Research Links grants within the field development research from the Swedish Research Council
Partnership country: India

In the modern world, the increasing demand of energy with increasing population and industrial growth has become a great concern. Although there is a vast resource of oil, natural gas and coal available on earth, their eco-friendly extraction and use often becomes problematic due to uncontrolled environmental pollution. At the same time, an alternative huge resource of energy is provided by the sun, which can meet all the demands of today’s society. However, the fundamental challenge is to develop methods to harvest solar energy in an efficient way. This leads to the exploration of photovoltaic and photocatalytic materials in developing solar cells, where the charge transfer processes through different complex pathways plays a fundamental role. It is extremely important to know the dynamics of these processes to develop better materials and suitable conditions for efficient conversion of solar energy to electrical and chemical energies. The understanding should emerge from a fundamental level where the dynamics of electrons and ions are describable by quantum mechanics.

In this proposal, we aim to develop a theoretical method that will enable us to study the dynamics of charge carriers along different pathways involved in chemical processes. This method will be based on time dependent density functional theory and non-adiabatic molecular dynamics where electronic and ionic motions are strongly coupled. Density functional theory, for which Walter Kohn has been awarded the Nobel prize in 1998, has been proved to be an extremely powerful method applied to several problems in physics, chemistry and biology. We will apply our developed method to study the charge transfer processes through the organic/inorganic interfaces, e.g., organometallics on TiO2 surfaces. Also, we will explore novel 2D materials, e.g., graphene and MoS2 for the suitability of solar cell applications. Graphene has been awarded the Nobel prize in 2010 for its extraordinary properties. It will be studied whether a combination of metallic graphene and semiconducting MoS2 can obstruct the recombination of electron and hole, which is required for efficient solar energy conversion. The outcome of this project will be highly beneficial for the fundamental understanding of charge transfer processes in many important technological applications and will help for better utilization of solar energy for future society.