Discovering Photocatalytic Materials From First Principles
Restricted (Penn State Only)
- Author:
- Hall, Nicole
- Graduate Program:
- Materials Science and Engineering
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- February 07, 2022
- Committee Members:
- John Mauro, Program Head/Chair
Raymond Schaak, Outside Unit & Field Member
Wesley Reinhart, Major Field Member
Susan Sinnott, Major Field Member
Ismaila Dabo, Chair & Dissertation Advisor - Keywords:
- Density-functional theory
Photocatalyst
DFT+U - Abstract:
- Hydrogen fuel is a promising renewable energy source, but the majority of current hydrogen production methods rely on fossil fuels. Photocatalysis offers a carbon neutral method of producing hydrogen gas, by using solar energy to split water into oxygen and hydrogen gases at the surface of semiconductor particles in solution. To facilitate the transition to photocatalysis as a renewable form of hydrogen production, there is a growing need for the discovery of low cost and high efficiency water-splitting photocatalysts. This dissertation centers around the discovery of novel water-splitting photocatalysts by advancing the implementation of first principles calculations in conjunction with high-throughput materials screenings. First, a benchmark study of density-functional theory with the Hubbard U correction (DFT+U) was conducted to determine calculation parameters for photocatalytic materials. In this benchmark, Hubbard corrections were applied to nontraditional states (e.g., light element p states), and nonorthogonalized and orthogonalized atomic orbitals were tested as Hubbard projector functions. Second, a high-throughput computational screening protocol was developed, which employs density-functional theory (DFT) and DFT+U methodologies to selectively screen for water-splitting photocatalysts. Lastly, we modified our high-throughput screening protocol to investigate alkali/alkaline-earth, p-block ternary oxides as water-splitting photocatalysts. These studies uncover novel photocatalytic materials, and thus support that DFT+U is a reliable electronic structure method for predicting band gaps towards the discovery of novel water-splitting photocatalysts.