title: Hazardous Doping for Photo-Electrochemical Conversion: The Case of Nb-Doped Fe₂O₃ from First Principles.
abstract: The challenge of improving the efficiency of photo-electrochemical devices is often addressed through doping. However, this strategy could harm performance. Specifically, as demonstrated in a recent experiment, doping one of the most widely used materials for water splitting, iron (III) oxide (Fe₂O₃), with niobium (Nb) can still result in limited efficiency. In order to better understand the hazardous effect of doping, we use Density Functional Theory (DFT)+U for the case of Nb-doped Fe₂O₃. We find a direct correlation between the charge of the dopant, the charge on surface of the Fe₂O₃ material, and the overpotential required for water oxidation reaction. We believe that this work contributes to advancing our understanding of how to select effective dopants for materials.
authors.affiliation: Department of Materials Science and Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel. nyatom@tx.technion.ac.il.
authors.forename: Natav
authors.initials: N
authors.lastname: Yatom
authors.affiliation: Department of Materials Science and Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel. maytalc@tx.technion.ac.il.
authors.forename: Maytal Caspary
authors.initials: MC
authors.lastname: Toroker
mesh_terms: D004563:Electrochemistry; D005290:Ferric Compounds / Q000737:chemistry*; D008962:Models, Theoretical; D009556:Niobium / Q000737:chemistry*; D010777:Photochemistry
chemical_list: D005290:Ferric Compounds; D009556:Niobium
keywords: DFT+U; Density Functional Theory; doping; iron oxides; water splitting