Computational insight into photo-induced processes at interfaces
There is enormous interest in understanding and controlling photo-induced charge transfer and chemical reactions for energy storage. These can be due either to water splitting and carbon dioxide reduction or by electro-hole pair separation at hybrid chromophore- or hybrid polymer-solid interfaces in photovoltaic devices, stimulating an increasing number of experimental and theoretical studies. Computational atomistic studies of experimental realistic setups require models that include an inorganic semiconductor nanostructure, acting as a catalyst and organic molecules in solvents. In photovoltaic applications, e.g. one has to consider multi-component systems, involving several chromophores tuned to absorb different wavelengths of light, an acceptor that removes an electron from the chromophores and creates separated electron-hole pairs, as well as electron and hole conducting media. Such models already may involve hundreds to thousands of atoms, extending far beyond the limits of any ab initio calculations. Furthermore, the non-equilibrium processes involved in the photo-induced charge separation and transport require explicit time domain modelling. Relevant processes occur on ultrafast time-scales and in most cases cannot be described by rate expressions. Charge separation, Auger-type energy exchange between electrons and holes, generation of additional charges by Auger mechanisms, energy losses to heat due to charge-phonon interactions, charge and energy transfer, and electron-hole recombination occur in parallel and competition requiring significant efforts in method development and clarification of multiple conceptual problems.
The proposed workshop should become a forum to brainstorm ideas about solutions to important computational problems and identify new directions for time-dependant electronic structure method development and challenging applications. In this way, we hope to create an exchange mechanism to unite a core of developers in an interactive environment to initiate design of a new generation software tools for quantum modelling of realistic complex systems in electronic ground and excited states. The delivery of this technology to a broad community would facilitate breakthroughs on high-impact materials science problems in pollutant degradation and photo-catalytic and photovoltaic energy storage.
This workshop brings together people from different communities working in photo-induced surface chemistry and photo-physics, to discuss a possible synergies and new ideas in development of quantum dynamical methods.
Computational materials sciences are outstanding growth areas of research. In the future an increasingly larger part of our technological development will depend on computer applications, in particular in materials, nano and bio-nano sciences. Ab-initio calculations based on the density functional theory in combination with the time-dependant extensions can make a considerable progress in the field increasing the photo-catalytic yield and the conversion efficiency of solar light into electricity. Furthermore, the non-equilibrium processes involved in the photo-induced charge separation and transport require explicit time domain modelling.
The scientific objectives of the proposed workshop are:
• Bring together researchers from quantum chemistry and computational solid state physics working on photo-catalysis and photovoltaics to highlight recent progress and discuss challenges and opportunities in the materials aspect of tailor-made nanostructures and hybrid interfaces for highly efficient energy applications.
• To foster the exchange of methodological expertise and new developments between scientists working on different aspects of metal oxide photo-catalysis.
• To discuss possibilities for optimizing the materials properties and device design. The interdisciplinary character of the workshop will help finding solutions for overcoming current limitations.
• Provide opportunity to form new worldwide interdisciplinary collaborations on computational photo-catalysis and photovoltaics for the mutual benefit of theoretical, experimental and applied researchers.
Sheng Meng ( Chinese Academy of Sciences, Beijing ) - Organiser & speaker
Thomas Frauenheim ( University of Bremen ) - Organiser
Johannes Lischner ( Imperial College London ) - Organiser
Oleg V. Prezhdo ( University of Southern California, Los Angeles ) - Organiser & speaker