TY - JOUR
T1 - Mixed excitonic nature in water-oxidized BiVO4 surfaces with defects
AU - Steinitz-Eliyahu, Rachel
AU - Hernangómez-Pérez, Daniel
AU - Hegner, Franziska
AU - Nikačević, Pavle
AU - López, Núria
AU - Refaely-Abramson, Sivan
N1 - Publisher Copyright: © 2022 American Physical Society.
PY - 2022/6/7
Y1 - 2022/6/7
N2 - BiVO4 is a promising photocatalyst for efficient water oxidation, with surface reactivity determined by the structure of active catalytic sites. Surface oxidation in the presence of oxygen vacancies induces electron localization, suggesting an atomistic route to improve the charge transfer efficiency within the catalytic cycle. In this paper, we study the effect of oxygen vacancies on the electronic and optical properties at BiVO4 surfaces upon water oxidation. We use density functional theory and many-body perturbation theory to explore the change in the electronic and quasiparticle energy levels and to evaluate the electron-hole coupling as a function of the underlying structure. We show that while the presence of defects alters the atomic structure and largely modifies the wave-function nature, leading to defect-localized states at the quasiparticle gap region, the optical excitations remain largely unchanged due to the substantial hybridization of defect and nondefect electron-hole transitions. Our findings suggest that defect-induced surface oxidation supports improved electron transport, both through bound and tunable electronic states and via a mixed nature of the optical transitions, expected to reduce electron-hole defect trapping.
AB - BiVO4 is a promising photocatalyst for efficient water oxidation, with surface reactivity determined by the structure of active catalytic sites. Surface oxidation in the presence of oxygen vacancies induces electron localization, suggesting an atomistic route to improve the charge transfer efficiency within the catalytic cycle. In this paper, we study the effect of oxygen vacancies on the electronic and optical properties at BiVO4 surfaces upon water oxidation. We use density functional theory and many-body perturbation theory to explore the change in the electronic and quasiparticle energy levels and to evaluate the electron-hole coupling as a function of the underlying structure. We show that while the presence of defects alters the atomic structure and largely modifies the wave-function nature, leading to defect-localized states at the quasiparticle gap region, the optical excitations remain largely unchanged due to the substantial hybridization of defect and nondefect electron-hole transitions. Our findings suggest that defect-induced surface oxidation supports improved electron transport, both through bound and tunable electronic states and via a mixed nature of the optical transitions, expected to reduce electron-hole defect trapping.
UR - http://www.scopus.com/inward/record.url?scp=85132848276&partnerID=8YFLogxK
U2 - https://doi.org/10.1103/PhysRevMaterials.6.065402
DO - https://doi.org/10.1103/PhysRevMaterials.6.065402
M3 - مقالة
SN - 2475-9953
VL - 6
JO - Physical Review Materials
JF - Physical Review Materials
IS - 6
M1 - 065402
ER -