Abstract In view of enhanced Pc applications, doped materials have drawn much attention. The present work focused on synthesizing pure and Pd doped WO3 Np, which were used as Pc for MB and RhB aqueous solutions discoloration, under VL, by a unique MWI technique. XRD and TEM studies revealed that Pd dopant did not influence WO3 samples structure and morphology, since they had mono-dispersed spherical forms, with an average diameter of about 50-30 nm. Optical spectra showed a red shift in the absorption edges, with an increase in Ct of Pd from 0 to 10 wt%, which indicates the decrease in Eg of WO3 with Pd doping. Eg was calculated as 3.02, 2.84 and 2.73 eV, for pure and Pd (5 and 10 wt%) doped WO3 samples, respectively. Pc intensity of Pd doped WO3 was significantly higher than that of the pure one. This was due to the recombination of photo-excited electrons and holes. Pc activities of pure and Pd doped WO3 samples were analyzed based on their ability to degrade MB and RhB dyes under VL. Pd doped WO3 showed better Pc degradation, due to an increase in SA, and a decrease in Eg and O vacancies.

Aluminium is the most widely used non ferrous metal. It is very needful to prevent this metal from corrosion .Corrosion inhibitors are one of the widely used methods to control corrosion. The purpose of this paper is to make people aware of organic corrosion inhibitors. Organic inhibitors are mainly present in natural products. It has been found that plant extracts and natural products show inhibition efficiency up to 98%. They are also non-toxic, eco-friendly, very cheaper. In the present work, natural products are used at various conditions and their inhibition efficiency is calculated by different methods; they obey various adsorption isotherms; the protective films formed by the inhibitors are analyzed by techniques such as electrochemical methods, FTIR, HPLC-RP, SEM, EDS.

The inhibition efficiency (IE) of phyllanthus amarus extract (PAE)-Zn2+ system, in controlling corrosion of carbon steel in an aqueous solution containing 60 ppm of Cl-, has been evaluated by weight loss method. Weight loss study reveals that the formulation consisting of 2 mL of PAE and 25 ppm of Zn2+ has 98% inhibition efficiency in controlling corrosion of carbon steel immersed in an aqueous solution containing 60 ppm of Cl-. Synergistic parameters suggest that a synergistic effect exists between PAE and Zn2+. Polarization study reveals that this system functions as mixed type of inhibitor controlling the cathodic reaction and anodic reaction to an equal extend. AC impedance spectra reveal that a protective film is formed on the metal surface. The FTIR spectra reveal that the protective film consists of Fe2+-phyllanthus complex.