The effect of cetyltrimethylammonium bromide on size and morphology of ZnO and CuO

The nanoparticles (NP) ZnO and CuO were synthesized by electrochemical-thermal method. The influence of cetyltrimethylammonium bromide (CTAB) on size and morphology of NP was evaluated. They were characterized by powder X-ray diffraction spectroscopy (XRD), scanning electron microscopy (SEM), UV-Visible absorption spectroscopy. The average crystallite size and the average grain size of NP decreased with CTAB concentration. The CTAB significantly affected the morphology of CuO and ZnO NP. The regular spindle shape of CuO transformed into irregular spherical shape and the homogeneity in the morphology of spherical ZnO NP was lost with increase in CTAB concentration. The effect of morphology and size of ZnO on its photocatalytic activity was evaluated by subjecting methylene blue (MB) dye to photocatalytic degradation under the irradiation of UV light. The color removal of MB dye during electrolysis was monitored by UV-Visible spectroscopy. The highest photocatalytic activity was noticed for ZnO 10 mM CTAB

Photostability of acetylated wood coated with nano zinc oxide

Chemical modification with acetic anhydride is an effective method to stabilise wood against dimensional movement and improve decay resistance of wood. It has also been reported to retard UV light induced color darkening on wood surface. Coatings of wood surfaces with certain nano metal oxides have also shown promise as UV screening agent. In this work, we have evaluated synergistic effect of acetylation of wood and application of nano material on wood surfaces to enhance their UV stability. Photo-stability of acetylated Wrightia tinctoria wood coated with zinc oxide (ZnO) nanodispersion was evaluated by irradiating these wood specimens to UV radiation in an accelerated weathering tester. Acetylation of wood with acetic anhydride exhibited photo-bleaching and inhibited light-induced color darkening observed in unmodified wood. Coating of unmodified and modified wood surfaces with ZnO nanodispersion reduced photo-discolouration and degradation of wood polymers. The photo-bleaching observed in chemically modified wood upon light irradiation was further enhanced by application of nano coating on wood surfaces

Electrochemical surface modification technique to impede mild steel corrosion using perfluorooctanoic acid

The present work demonstrated that corrosion inhibition efficiency of electrochemically generated organic coat is remarkably more effective than self-assembled monolayer (SAM) generated by dip coating technique. Perfluorooctanoic acid (PFOA) is used to modify mild steel surface for effective protection. Infrared reflection absorption spectroscopy and contact angle measurements substantiate the modification of mild steel surface and its effect on surface hydrophobicity. A comparison between electrochemical properties of PFOA SAM generated by dip coat method (DC-PFOA) and PFOA coat generated by electrochemical method (EC-PFOA) is presented. Electrochemical measurements reveal that the corrosion protection efficiency of EC-PFOA (91 %) is much superior to DC-PFOA (28 %)

Photostability of acetylated wood coated with nano zinc oxide

Chemical modification with acetic anhydride is an effective method to stabilise wood against dimensional movement and improve decay resistance of wood. It has also been reported to retard UV light induced color darkening on wood surface. Coatings of wood surfaces with certain nano metal oxides have also shown promise as UV screening agent.In this work, we have evaluated synergistic effect of acetylation of wood and application of nano material on wood surfaces to enhance their UV stability. Photo-stability of acetylated Wrightia tinctoria wood coated with zinc oxide (ZnO) nanodispersion was evaluated by irradiating these wood specimens to UV radiation in an accelerated weathering tester. Acetylation of wood with acetic anhydride exhibited photo-bleaching and inhibited light-induced color darkening observed in unmodified wood. Coating of unmodified and modified wood surfaces with ZnO nanodispersion reduced photo-discolouration and degradation of wood polymers. The photo-bleaching observed in chemically modified wood upon light irradiation was further enhanced by application of nano coating on wood surface

Anticorrosive behaviour of lumefantrine hydrophobic layer on mild steel surface

The surface modification of mild steel was achieved by chemical treatment in lumefantrine (LF) solution. The surface morphology and wettability of modified surface was analysed by 3D profilometer and contact angle goniometer. The corrosion inhibition performance of modified mild steel surface in 1.0 M HCl solution was investigated by potentiodynamic polarization and electrochemical impedance techniques.Electroche­mical measurements illustrate that the corrosion of mild steel in acidic chloride medium get substantially reduced by introducing LF film on its surface (94 % efficiency). Quantum chemical parameters were evaluated by ab initio method and they confer appropriate theoretical support to the experimental findings