Plasma Electrolytic Oxidation (PEO) is a surface treatment process that has been extensively studied in recent years for its ability to produce thick, dense metal oxide coatings. This process is especially effective on light metals, primarily enhancing their wear and corrosion resistance. Recently, the PEO process has also been used to produce composite coatings by adding luminescent nanoparticles to the electrolyte. This work presents the spectroscopic properties of PEO coatings on light metal alloys with luminescent particle additions. To increase the functionality of these coatings, various phosphors were incorporated, thereby enhancing their functional capabilities. The coatings’ structure and morphology were characterized using X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM), both on the surface and in cross-section. Additionally, the chemical composition of the layers was analyzed using Glow Discharge Optical Emission Spectroscopy (GDOES) and Energy-Dispersive Spectroscopy (EDS) on both the surface and cross-sections. The photocatalytic properties of the coatings were evaluated on samples containing graphene@TiO2 particles by monitoring the photodegradation of bisphenol A using UV-Vis absorption spectroscopy. For temperature-sensing properties, Er0.02Yb0.4Y1.58O3 additives were tested. Contactless temperature measurements were conducted across a broad temperature range to determine the most effective range for practical use. Furthermore, SiO-CaO glasses doped with Yb3+/Er3+ ions were utilized to prepare coatings on alloys that were intended for implant applications. These coatings were assessed for their ability to monitor layer bioactivity and the growth of hydroxyapatite, which is crucial for implant integration and functionality.
It was shown that the incorporation of various luminescent additives into the PEO electrolyte for coating light metal alloys enhances a surface's mechanical properties and introduces new functionalities for a wide range of optical applications.
Acknowledgements
The studies were funded from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 823942–FUNCOAT–H2020-MSCA-RISE-2018
