April 2017: Dr Claudio Cazorla Silva, "Lattice effects on the formation of oxygen vacancies in perovskite thin films"
Vacancies job in oxides design
Crystalline defects may confer new properties to multifunctional materials, including magnetism, enhaced catalytic activity, and conductivity. Creating defects in a controlled manner, therefore, emerges as a new promising avenue for the rational design of novel materials with superior qualities. In particular, oxygen vacancies are known to affect considerably the multifunctional properties of oxide perovskites; however, these are normally created without any govern during the synthesis process of the material. Recently, epitaxial strain has been proposed as an effective means to control the concentration of defects in oxide perovskites. Unfortunately, it is difficult, if not impossible, to gain quantitative microscopic insight into the relation between epitaxial strain and formation energy of vacancies directly from the experiments. In this work, I start filling this knowledge gap by performing first-principles simulations based on density functional theory. Specifically, I substantiate the effects of thermal lattice excitations on the formation energy of vacancies in oxides thin films.
Read the full article, as published in Physical Review Applied (Volume 7, Issue 4, 2017).