Ellipsometry‐Based Approach for the Characterization of Mesoporous Thin Films for H₂ Technologies

Porous thin layer materials are gaining importance in different fields of technology and pose a challenge to the accurate determination of materials’ properties important for their function. Herein, a hybrid measurement technique using ellipsometry together with other independent methods for validation, is demonstrated. Ellipsometry provides information about the porosity of different mesoporous films (PtRuNP/OMC = 45%; IrO_x = 46%) as well as about the pore size (pore radius of ≈5 nm for PtRuNP/OMC). In addition, the electronic structure of a material, such as intraband transitions of a mesoporous IrO_x film, can be identified, which can be used to better understand the mechanisms of chemical processes. In addition, it is shown that ellipsometry can be used as a scalable imaging and visualization method for quality assurance in production. These require accurate and traceable measurements, with reference materials playing an important role that include porosity and other related properties. It is shown that novel analytical methods are useful for improving analytical work in this entire field.