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Niobium powder was fabricated by metallothermic reduction process using K₂NbF₇ as the raw material, KCl and KF as the diluents and Na as the reducing agent. The apparatus for the experiment was designed and built specifically for the present study. Varying properties of niobium powder depending on reaction temperature and excess of reducing agent were analyzed. The niobium particle size increased significantly as the reduction temperature increased from 993 to 1093 K. The particle size was fairly uniform at a given reaction temperature, varying from 0.2 μ m to 50 nm depending on the reaction temperature. The yield of niobium powder increased from 58 to 83% with an increase in reaction temperature. The average particle size of niobium powder was improved from 70 nm to 0.2 μ m with the increase in the amount of Na excess. In addition, the yield rate of Nb powder was 82% in the 5% excess sodium.

A precipitation–reduction synthesis method for silver nanoparticles (Ag NPs) was developed. Molten ε-caprolactam (CL) was used not only as solvent but also as reducing agent and stabilizer. At first, Ag₂O NPs was prepared by precipitation reaction of silver nitrate (AgNO₃) and sodium hydroxide (NaOH) using molten CL as solvent at 100°C. Then, Ag₂O NPs was in situ reduced into Ag NPs by molten CL at 120°C. Techniques of X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to monitor the synthesis process. With the increase of reduction time, monodispersed Ag₂O NPs (ca. 3.7 nm) were integrated and larger Ag NPs (10–90 nm) were formed. Fourier transform infrared (FT-IR) results showed that the surface of Ag NPs was capped with about 0.9 wt.% of CL molecules. Surface enhanced Raman scattering (SERS) effect of Ag NPs was investigated using Rhodamine 6G as a probe molecule.

Silver-doped zinc oxide nanoparticles (NPs) were synthesized employing a facile hydrothermal method supported by the seaweed Turbinaria ornata (TO). TO extract was used as a capping agent. The prepared NPs were accounted for using instrumentational analysis such as FE-SEM, EDS, XRD, FTIR, and UV-Vis. Their characteristic study showed an average size of 26 nm with 81% crystallinity with X-ray Diffraction and the band-gap value as 3.25 eV. The biosynthesized doped particle exhibited rod-shaped morphology for better efficiency in dye degradation of Methylene Blue (MB) dye. They were also tested for adsorption kinetics and photocatalytic degradation of MB using sunlight. The efficiency in degrading the MB dye proclaimed a remarkable change in solar irradiation of about 90% reduction to visible light, which leads to the betterment in solar degradation of dye pollutants at a minimal cost.