Instructors: Edgardo Saucedo, Catalonia Institute for Energy Research; Joel W. Ager, Lawrence Berkeley National Laboratory; Daniel Davies, University College London; Stephan Lany, National Renewable Energy Laboratory
The goal of this tutorial is to familiarize young scientists with research methods and best practices in the field of Emerging Inorganic Semiconductors for Solar-Energy Conversion. To meet this objective, the tutorial will have two parts, on experimental and computational methods, respectively. The experimental part of the tutorial will focus on emerging inorganic absorber materials for photovoltaic and photoelectrochemical solar-cell application. Topics covered for both of these applications include the target materials properties, chemical classes of studied materials and best practices in device efficiency measurements. The computational part of the tutorial will focus on methods for data-driven screening and for simulations of disorder. Covered topics include predicting the structure and evaluating the stability for inorganic materials, both ordered and disordered, and calculating the resulting electronic structure and charge-transport properties.
Edgardo Saucedo, Catalonia Institute for Energy Research
This section will include a discussion and description of different classes of PV emerging materials, including oxides, chalcogenides, pnictides and halides. The most notable cases available in the literature will be highlighted and presented in detail. In addition, the desired bulk and interface properties of emerging PV materials (e.g., lifetimes, band alignments) will be discussed, giving insights into how to select a good candidate for PV applications. Finally, state-of-the-art conversion efficiency of emerging PV materials will be reviewed, and best practices for PV measurements will be presented.
10:00 am BREAK
Joel W. Ager, Lawrence Berkeley National Laboratory
This section will cover methods used to evaluate the functionality of photoelectrochemical (PEC) systems for water splitting and CO2 reductions. Best practices for both half-cell (e.g., water oxidation, hydrogen evolution reactions) and full-cell experiments will be discussed. Analytical methods for measuring the products of carbon dioxide reduction will be presented, and best practices for calculation of faradaic and overall energy-conversion efficiencies will be discussed. Methods to evaluate stability and to determine degradation mechanisms will also be presented.
Daniel Davies, University College London
This section will cover practical computational tools and techniques for exploring new chemical compositions and crystal structures. We will focus on computationally affordable, data-driven methods such as supervised machine learning that can be used on a desktop computer to screen for compounds with target optoelectronic properties. The aim is to give participants an insight into the strengths and limitations of these techniques, and show how they can be used to complement targeted computations.
3:00 pm BREAK
Stephan Lany, National Renewable Energy Laboratory
This section will review computational methods and their applications for the study of disorder in ternary and multinary semiconductors. Cation disorder impacts the optical, electrical and transport properties of materials, with profound implications for photovoltaic and other energy applications. We will discuss various aspects of computational modeling, including Monte Carlo simulations with model Hamiltonians, electronic structure calculations and defects in the presence of disorder.