Materials Science Forum Vol. 1173

Abstract: In this article, we propose a biosensor based on a hybrid photonic crystal, the studied system is a superlattice consisting of a periodic alternation of poly(methyl methacrylate) (PMMA) and silicon dioxide (SiO₂) layers. Our study demonstrates that breaking the periodicity of the superlattice enables the excitation of Bloch surface waves within the photonic bandgap. This feature, along with its experimental convenience, justifies our choice of this structure for designing a biosensor in the Kretschmann configuration. Furthermore, we also analyzed the effect of various parameters, such as the number of layer repetitions, the frequency of the light waves used, and the thickness of the defect layer, on the biosensor's performance, the optimal structure, MgF₂/(PMMA/SiO₂)₃/D, demonstrates excellent sensing performance, achieving an angular sensitivity of 74°/RIU and a high figure of merit (FOM) of 1495/RIU.

Abstract: Regeneration of industrial catalysts is a better way of increasing the catalytic activity of a catalyst. These catalysts are used in the production of sulfuric acid, in the conversion of sulfur dioxide to sulfur trioxide. They lose their efficiency and activity over time, so it is preferable to regenerate the catalyst instead of discarding it as waste, using a thermal regeneration method followed by chemical treatment by impregnation with different percentages of V₂O₅, 10%, 20% and 30%. They are then examined using techniques known as XRD and FTIR. The IR spectrum shows that the catalyst doped with 30% V₂O₅ has the same bands as the fresh catalyst. Finally, the catalytic test carried out by iodometric assay shows that the catalyst regenerated with 20% V₂O₅ has a conversion rate of 63%, identical to that of fresh catalyst.

Abstract: Carbon nitride (C₃N₄) has gained attention from scientists due to its potential applications as a catalyst for organic synthesis, electrodes, photocatalysts, and hydrogen storage materials. Using C₃N₄ as a photocatalyst for the glycerol-to-hydrogen reaction could offer many development advantages. Pure C₃N₄ has several shortcomings as a photocatalyst, so modifications are needed to enhance its properties and characteristics. Converting C₃N₄ into nanosheet form and adding Zirconium doping are solutions to improve its performance. The nanosheet form increases the surface area by creating thin sheet structures, while Zirconium doping is chosen because it can improve the conductivity and mechanical properties of the catalyst. This research focuses on characterizing catalysts with varying doping levels (5%, 10%, 15%, 20%, and 27%). Tests conducted include BET analysis, XRD, and UV-Vis DRS. Results show that the sample with 20% doping performs the best, with a specific surface area of 46.087 m²/g. Crystallinity was assessed with values of 2Ө = 27.8426°, 31.6712°, 45.4188°, and 56.4368°. The band gap energy was determined to be 3.067 eV. These findings are then compared with previous research.