Demonstrates lattice behavior in perovskite oxides with dopants and oxygen vacancies, suggesting new pathways for energy applications.
Key Points
The aim is to understand how La doping and oxygen vacancies affect the lattice structure of perovskite oxides and to connect experimental findings with theoretical models.
Synthesize SrTiO3 and La-doped SrTiO3 with varying La fractions
Perform thermal treatments in oxidizing and reducing atmospheres
Utilize X-ray diffraction for structural analysis
Conduct density functional theory calculations including A-site and oxygen vacancies
La doping contracts the lattice while reduction leads to oxygen-vacancy-driven expansion
Oxygen nonstoichiometry was quantified showing a significant increase in oxygen deficiency
The band gap reduced from 3.7-3.9 eV to 1.2-1.6 eV due to La-dopant interactions
An almost constant per-vacancy expansion coefficient was established, supporting the additive lattice response