Coating on Steel Discs with a Photocatalytic System CuO/SiO2 for the Degradation of the Ubiquitous Contaminants Methylene Blue and Amoxicillin

The present research work describes the synthesis and characterization of CuO/SiO2 for coating-perforated 304 stainless steel (SS) substrates to degrade methylene blue and amoxicillin under visible light irradiation. The foregoing photocatalytic system was achieved through the coprecipitation method by adding pure CuO to a SiO2 sol at 1:5, 1:10, and 1:15 molar ratios. The conditions for carrying out the depositions on the SS substrates (three per substrate) involved an immersion rate of 90 mm/min with a drying time of 20 min at 120 °C. The XRD technique confirmed the presence of the SiO2 amorphous phases and CuO monoclinic systems in the coatings, with a particle size distribution ranging from 0.5 to 2.5 μm (with an average of 1.26 ± 0.06 μm). As for SEM, it revealed a homogeneous coating surface without cracks. The produced photoactive CuO/SiO2 coatings were capable of degrading methylene blue (98%) at 1500 min and amoxicillin (55%) at 450 min.